diff --git a/vendor/github.com/golang/protobuf/proto/clone.go b/vendor/github.com/golang/protobuf/proto/clone.go
index e98ddec..e392575 100644
--- a/vendor/github.com/golang/protobuf/proto/clone.go
+++ b/vendor/github.com/golang/protobuf/proto/clone.go
@@ -84,9 +84,15 @@ func mergeStruct(out, in reflect.Value) {
 		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
 	}
 
-	if emIn, ok := in.Addr().Interface().(extendableProto); ok {
-		emOut := out.Addr().Interface().(extendableProto)
-		mergeExtension(emOut.ExtensionMap(), emIn.ExtensionMap())
+	if emIn, ok := extendable(in.Addr().Interface()); ok {
+		emOut, _ := extendable(out.Addr().Interface())
+		mIn, muIn := emIn.extensionsRead()
+		if mIn != nil {
+			mOut := emOut.extensionsWrite()
+			muIn.Lock()
+			mergeExtension(mOut, mIn)
+			muIn.Unlock()
+		}
 	}
 
 	uf := in.FieldByName("XXX_unrecognized")
diff --git a/vendor/github.com/golang/protobuf/proto/decode.go b/vendor/github.com/golang/protobuf/proto/decode.go
index f94b9f4..aa20729 100644
--- a/vendor/github.com/golang/protobuf/proto/decode.go
+++ b/vendor/github.com/golang/protobuf/proto/decode.go
@@ -61,7 +61,6 @@ var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for
 // int32, int64, uint32, uint64, bool, and enum
 // protocol buffer types.
 func DecodeVarint(buf []byte) (x uint64, n int) {
-	// x, n already 0
 	for shift := uint(0); shift < 64; shift += 7 {
 		if n >= len(buf) {
 			return 0, 0
@@ -78,13 +77,7 @@ func DecodeVarint(buf []byte) (x uint64, n int) {
 	return 0, 0
 }
 
-// DecodeVarint reads a varint-encoded integer from the Buffer.
-// This is the format for the
-// int32, int64, uint32, uint64, bool, and enum
-// protocol buffer types.
-func (p *Buffer) DecodeVarint() (x uint64, err error) {
-	// x, err already 0
-
+func (p *Buffer) decodeVarintSlow() (x uint64, err error) {
 	i := p.index
 	l := len(p.buf)
 
@@ -107,6 +100,107 @@ func (p *Buffer) DecodeVarint() (x uint64, err error) {
 	return
 }
 
+// DecodeVarint reads a varint-encoded integer from the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) DecodeVarint() (x uint64, err error) {
+	i := p.index
+	buf := p.buf
+
+	if i >= len(buf) {
+		return 0, io.ErrUnexpectedEOF
+	} else if buf[i] < 0x80 {
+		p.index++
+		return uint64(buf[i]), nil
+	} else if len(buf)-i < 10 {
+		return p.decodeVarintSlow()
+	}
+
+	var b uint64
+	// we already checked the first byte
+	x = uint64(buf[i]) - 0x80
+	i++
+
+	b = uint64(buf[i])
+	i++
+	x += b << 7
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 7
+
+	b = uint64(buf[i])
+	i++
+	x += b << 14
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 14
+
+	b = uint64(buf[i])
+	i++
+	x += b << 21
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 21
+
+	b = uint64(buf[i])
+	i++
+	x += b << 28
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 28
+
+	b = uint64(buf[i])
+	i++
+	x += b << 35
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 35
+
+	b = uint64(buf[i])
+	i++
+	x += b << 42
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 42
+
+	b = uint64(buf[i])
+	i++
+	x += b << 49
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 49
+
+	b = uint64(buf[i])
+	i++
+	x += b << 56
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 56
+
+	b = uint64(buf[i])
+	i++
+	x += b << 63
+	if b&0x80 == 0 {
+		goto done
+	}
+	// x -= 0x80 << 63 // Always zero.
+
+	return 0, errOverflow
+
+done:
+	p.index = i
+	return x, nil
+}
+
 // DecodeFixed64 reads a 64-bit integer from the Buffer.
 // This is the format for the
 // fixed64, sfixed64, and double protocol buffer types.
@@ -340,6 +434,8 @@ func (p *Buffer) DecodeGroup(pb Message) error {
 // Buffer and places the decoded result in pb.  If the struct
 // underlying pb does not match the data in the buffer, the results can be
 // unpredictable.
+//
+// Unlike proto.Unmarshal, this does not reset pb before starting to unmarshal.
 func (p *Buffer) Unmarshal(pb Message) error {
 	// If the object can unmarshal itself, let it.
 	if u, ok := pb.(Unmarshaler); ok {
@@ -378,6 +474,11 @@ func (o *Buffer) unmarshalType(st reflect.Type, prop *StructProperties, is_group
 		wire := int(u & 0x7)
 		if wire == WireEndGroup {
 			if is_group {
+				if required > 0 {
+					// Not enough information to determine the exact field.
+					// (See below.)
+					return &RequiredNotSetError{"{Unknown}"}
+				}
 				return nil // input is satisfied
 			}
 			return fmt.Errorf("proto: %s: wiretype end group for non-group", st)
@@ -390,11 +491,12 @@ func (o *Buffer) unmarshalType(st reflect.Type, prop *StructProperties, is_group
 		if !ok {
 			// Maybe it's an extension?
 			if prop.extendable {
-				if e := structPointer_Interface(base, st).(extendableProto); isExtensionField(e, int32(tag)) {
+				if e, _ := extendable(structPointer_Interface(base, st)); isExtensionField(e, int32(tag)) {
 					if err = o.skip(st, tag, wire); err == nil {
-						ext := e.ExtensionMap()[int32(tag)] // may be missing
+						extmap := e.extensionsWrite()
+						ext := extmap[int32(tag)] // may be missing
 						ext.enc = append(ext.enc, o.buf[oi:o.index]...)
-						e.ExtensionMap()[int32(tag)] = ext
+						extmap[int32(tag)] = ext
 					}
 					continue
 				}
diff --git a/vendor/github.com/golang/protobuf/proto/encode.go b/vendor/github.com/golang/protobuf/proto/encode.go
index eb7e047..8b84d1b 100644
--- a/vendor/github.com/golang/protobuf/proto/encode.go
+++ b/vendor/github.com/golang/protobuf/proto/encode.go
@@ -70,6 +70,10 @@ var (
 
 	// ErrNil is the error returned if Marshal is called with nil.
 	ErrNil = errors.New("proto: Marshal called with nil")
+
+	// ErrTooLarge is the error returned if Marshal is called with a
+	// message that encodes to >2GB.
+	ErrTooLarge = errors.New("proto: message encodes to over 2 GB")
 )
 
 // The fundamental encoders that put bytes on the wire.
@@ -78,6 +82,10 @@ var (
 
 const maxVarintBytes = 10 // maximum length of a varint
 
+// maxMarshalSize is the largest allowed size of an encoded protobuf,
+// since C++ and Java use signed int32s for the size.
+const maxMarshalSize = 1<<31 - 1
+
 // EncodeVarint returns the varint encoding of x.
 // This is the format for the
 // int32, int64, uint32, uint64, bool, and enum
@@ -166,11 +174,11 @@ func sizeFixed32(x uint64) int {
 // This is the format used for the sint64 protocol buffer type.
 func (p *Buffer) EncodeZigzag64(x uint64) error {
 	// use signed number to get arithmetic right shift.
-	return p.EncodeVarint(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+	return p.EncodeVarint((x << 1) ^ uint64((int64(x) >> 63)))
 }
 
 func sizeZigzag64(x uint64) int {
-	return sizeVarint(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+	return sizeVarint((x << 1) ^ uint64((int64(x) >> 63)))
 }
 
 // EncodeZigzag32 writes a zigzag-encoded 32-bit integer
@@ -226,10 +234,6 @@ func Marshal(pb Message) ([]byte, error) {
 	}
 	p := NewBuffer(nil)
 	err := p.Marshal(pb)
-	var state errorState
-	if err != nil && !state.shouldContinue(err, nil) {
-		return nil, err
-	}
 	if p.buf == nil && err == nil {
 		// Return a non-nil slice on success.
 		return []byte{}, nil
@@ -258,11 +262,8 @@ func (p *Buffer) Marshal(pb Message) error {
 	// Can the object marshal itself?
 	if m, ok := pb.(Marshaler); ok {
 		data, err := m.Marshal()
-		if err != nil {
-			return err
-		}
 		p.buf = append(p.buf, data...)
-		return nil
+		return err
 	}
 
 	t, base, err := getbase(pb)
@@ -274,9 +275,12 @@ func (p *Buffer) Marshal(pb Message) error {
 	}
 
 	if collectStats {
-		stats.Encode++
+		(stats).Encode++ // Parens are to work around a goimports bug.
 	}
 
+	if len(p.buf) > maxMarshalSize {
+		return ErrTooLarge
+	}
 	return err
 }
 
@@ -298,7 +302,7 @@ func Size(pb Message) (n int) {
 	}
 
 	if collectStats {
-		stats.Size++
+		(stats).Size++ // Parens are to work around a goimports bug.
 	}
 
 	return
@@ -1003,7 +1007,6 @@ func size_slice_struct_message(p *Properties, base structPointer) (n int) {
 		if p.isMarshaler {
 			m := structPointer_Interface(structp, p.stype).(Marshaler)
 			data, _ := m.Marshal()
-			n += len(p.tagcode)
 			n += sizeRawBytes(data)
 			continue
 		}
@@ -1062,10 +1065,32 @@ func size_slice_struct_group(p *Properties, base structPointer) (n int) {
 
 // Encode an extension map.
 func (o *Buffer) enc_map(p *Properties, base structPointer) error {
-	v := *structPointer_ExtMap(base, p.field)
-	if err := encodeExtensionMap(v); err != nil {
+	exts := structPointer_ExtMap(base, p.field)
+	if err := encodeExtensionsMap(*exts); err != nil {
 		return err
 	}
+
+	return o.enc_map_body(*exts)
+}
+
+func (o *Buffer) enc_exts(p *Properties, base structPointer) error {
+	exts := structPointer_Extensions(base, p.field)
+
+	v, mu := exts.extensionsRead()
+	if v == nil {
+		return nil
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	if err := encodeExtensionsMap(v); err != nil {
+		return err
+	}
+
+	return o.enc_map_body(v)
+}
+
+func (o *Buffer) enc_map_body(v map[int32]Extension) error {
 	// Fast-path for common cases: zero or one extensions.
 	if len(v) <= 1 {
 		for _, e := range v {
@@ -1088,8 +1113,13 @@ func (o *Buffer) enc_map(p *Properties, base structPointer) error {
 }
 
 func size_map(p *Properties, base structPointer) int {
-	v := *structPointer_ExtMap(base, p.field)
-	return sizeExtensionMap(v)
+	v := structPointer_ExtMap(base, p.field)
+	return extensionsMapSize(*v)
+}
+
+func size_exts(p *Properties, base structPointer) int {
+	v := structPointer_Extensions(base, p.field)
+	return extensionsSize(v)
 }
 
 // Encode a map field.
@@ -1118,7 +1148,7 @@ func (o *Buffer) enc_new_map(p *Properties, base structPointer) error {
 		if err := p.mkeyprop.enc(o, p.mkeyprop, keybase); err != nil {
 			return err
 		}
-		if err := p.mvalprop.enc(o, p.mvalprop, valbase); err != nil {
+		if err := p.mvalprop.enc(o, p.mvalprop, valbase); err != nil && err != ErrNil {
 			return err
 		}
 		return nil
@@ -1128,11 +1158,6 @@ func (o *Buffer) enc_new_map(p *Properties, base structPointer) error {
 	for _, key := range v.MapKeys() {
 		val := v.MapIndex(key)
 
-		// The only illegal map entry values are nil message pointers.
-		if val.Kind() == reflect.Ptr && val.IsNil() {
-			return errors.New("proto: map has nil element")
-		}
-
 		keycopy.Set(key)
 		valcopy.Set(val)
 
@@ -1220,6 +1245,9 @@ func (o *Buffer) enc_struct(prop *StructProperties, base structPointer) error {
 					return err
 				}
 			}
+			if len(o.buf) > maxMarshalSize {
+				return ErrTooLarge
+			}
 		}
 	}
 
@@ -1236,6 +1264,9 @@ func (o *Buffer) enc_struct(prop *StructProperties, base structPointer) error {
 	// Add unrecognized fields at the end.
 	if prop.unrecField.IsValid() {
 		v := *structPointer_Bytes(base, prop.unrecField)
+		if len(o.buf)+len(v) > maxMarshalSize {
+			return ErrTooLarge
+		}
 		if len(v) > 0 {
 			o.buf = append(o.buf, v...)
 		}
diff --git a/vendor/github.com/golang/protobuf/proto/equal.go b/vendor/github.com/golang/protobuf/proto/equal.go
index f5db1de..2ed1cf5 100644
--- a/vendor/github.com/golang/protobuf/proto/equal.go
+++ b/vendor/github.com/golang/protobuf/proto/equal.go
@@ -54,13 +54,17 @@ Equality is defined in this way:
     in a proto3 .proto file, fields are not "set"; specifically,
     zero length proto3 "bytes" fields are equal (nil == {}).
   - Two repeated fields are equal iff their lengths are the same,
-    and their corresponding elements are equal (a "bytes" field,
-    although represented by []byte, is not a repeated field)
+    and their corresponding elements are equal. Note a "bytes" field,
+    although represented by []byte, is not a repeated field and the
+    rule for the scalar fields described above applies.
   - Two unset fields are equal.
   - Two unknown field sets are equal if their current
     encoded state is equal.
   - Two extension sets are equal iff they have corresponding
     elements that are pairwise equal.
+  - Two map fields are equal iff their lengths are the same,
+    and they contain the same set of elements. Zero-length map
+    fields are equal.
   - Every other combination of things are not equal.
 
 The return value is undefined if a and b are not protocol buffers.
@@ -121,9 +125,16 @@ func equalStruct(v1, v2 reflect.Value) bool {
 		}
 	}
 
+	if em1 := v1.FieldByName("XXX_InternalExtensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_InternalExtensions")
+		if !equalExtensions(v1.Type(), em1.Interface().(XXX_InternalExtensions), em2.Interface().(XXX_InternalExtensions)) {
+			return false
+		}
+	}
+
 	if em1 := v1.FieldByName("XXX_extensions"); em1.IsValid() {
 		em2 := v2.FieldByName("XXX_extensions")
-		if !equalExtensions(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
+		if !equalExtMap(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
 			return false
 		}
 	}
@@ -184,6 +195,13 @@ func equalAny(v1, v2 reflect.Value, prop *Properties) bool {
 		}
 		return true
 	case reflect.Ptr:
+		// Maps may have nil values in them, so check for nil.
+		if v1.IsNil() && v2.IsNil() {
+			return true
+		}
+		if v1.IsNil() != v2.IsNil() {
+			return false
+		}
 		return equalAny(v1.Elem(), v2.Elem(), prop)
 	case reflect.Slice:
 		if v1.Type().Elem().Kind() == reflect.Uint8 {
@@ -223,8 +241,14 @@ func equalAny(v1, v2 reflect.Value, prop *Properties) bool {
 }
 
 // base is the struct type that the extensions are based on.
-// em1 and em2 are extension maps.
-func equalExtensions(base reflect.Type, em1, em2 map[int32]Extension) bool {
+// x1 and x2 are InternalExtensions.
+func equalExtensions(base reflect.Type, x1, x2 XXX_InternalExtensions) bool {
+	em1, _ := x1.extensionsRead()
+	em2, _ := x2.extensionsRead()
+	return equalExtMap(base, em1, em2)
+}
+
+func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
 	if len(em1) != len(em2) {
 		return false
 	}
diff --git a/vendor/github.com/golang/protobuf/proto/extensions.go b/vendor/github.com/golang/protobuf/proto/extensions.go
index 054f4f1..eaad218 100644
--- a/vendor/github.com/golang/protobuf/proto/extensions.go
+++ b/vendor/github.com/golang/protobuf/proto/extensions.go
@@ -52,14 +52,99 @@ type ExtensionRange struct {
 	Start, End int32 // both inclusive
 }
 
-// extendableProto is an interface implemented by any protocol buffer that may be extended.
+// extendableProto is an interface implemented by any protocol buffer generated by the current
+// proto compiler that may be extended.
 type extendableProto interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	extensionsWrite() map[int32]Extension
+	extensionsRead() (map[int32]Extension, sync.Locker)
+}
+
+// extendableProtoV1 is an interface implemented by a protocol buffer generated by the previous
+// version of the proto compiler that may be extended.
+type extendableProtoV1 interface {
 	Message
 	ExtensionRangeArray() []ExtensionRange
 	ExtensionMap() map[int32]Extension
 }
 
+// extensionAdapter is a wrapper around extendableProtoV1 that implements extendableProto.
+type extensionAdapter struct {
+	extendableProtoV1
+}
+
+func (e extensionAdapter) extensionsWrite() map[int32]Extension {
+	return e.ExtensionMap()
+}
+
+func (e extensionAdapter) extensionsRead() (map[int32]Extension, sync.Locker) {
+	return e.ExtensionMap(), notLocker{}
+}
+
+// notLocker is a sync.Locker whose Lock and Unlock methods are nops.
+type notLocker struct{}
+
+func (n notLocker) Lock()   {}
+func (n notLocker) Unlock() {}
+
+// extendable returns the extendableProto interface for the given generated proto message.
+// If the proto message has the old extension format, it returns a wrapper that implements
+// the extendableProto interface.
+func extendable(p interface{}) (extendableProto, bool) {
+	if ep, ok := p.(extendableProto); ok {
+		return ep, ok
+	}
+	if ep, ok := p.(extendableProtoV1); ok {
+		return extensionAdapter{ep}, ok
+	}
+	return nil, false
+}
+
+// XXX_InternalExtensions is an internal representation of proto extensions.
+//
+// Each generated message struct type embeds an anonymous XXX_InternalExtensions field,
+// thus gaining the unexported 'extensions' method, which can be called only from the proto package.
+//
+// The methods of XXX_InternalExtensions are not concurrency safe in general,
+// but calls to logically read-only methods such as has and get may be executed concurrently.
+type XXX_InternalExtensions struct {
+	// The struct must be indirect so that if a user inadvertently copies a
+	// generated message and its embedded XXX_InternalExtensions, they
+	// avoid the mayhem of a copied mutex.
+	//
+	// The mutex serializes all logically read-only operations to p.extensionMap.
+	// It is up to the client to ensure that write operations to p.extensionMap are
+	// mutually exclusive with other accesses.
+	p *struct {
+		mu           sync.Mutex
+		extensionMap map[int32]Extension
+	}
+}
+
+// extensionsWrite returns the extension map, creating it on first use.
+func (e *XXX_InternalExtensions) extensionsWrite() map[int32]Extension {
+	if e.p == nil {
+		e.p = new(struct {
+			mu           sync.Mutex
+			extensionMap map[int32]Extension
+		})
+		e.p.extensionMap = make(map[int32]Extension)
+	}
+	return e.p.extensionMap
+}
+
+// extensionsRead returns the extensions map for read-only use.  It may be nil.
+// The caller must hold the returned mutex's lock when accessing Elements within the map.
+func (e *XXX_InternalExtensions) extensionsRead() (map[int32]Extension, sync.Locker) {
+	if e.p == nil {
+		return nil, nil
+	}
+	return e.p.extensionMap, &e.p.mu
+}
+
 var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem()
+var extendableProtoV1Type = reflect.TypeOf((*extendableProtoV1)(nil)).Elem()
 
 // ExtensionDesc represents an extension specification.
 // Used in generated code from the protocol compiler.
@@ -69,6 +154,7 @@ type ExtensionDesc struct {
 	Field         int32       // field number
 	Name          string      // fully-qualified name of extension, for text formatting
 	Tag           string      // protobuf tag style
+	Filename      string      // name of the file in which the extension is defined
 }
 
 func (ed *ExtensionDesc) repeated() bool {
@@ -92,8 +178,13 @@ type Extension struct {
 }
 
 // SetRawExtension is for testing only.
-func SetRawExtension(base extendableProto, id int32, b []byte) {
-	base.ExtensionMap()[id] = Extension{enc: b}
+func SetRawExtension(base Message, id int32, b []byte) {
+	epb, ok := extendable(base)
+	if !ok {
+		return
+	}
+	extmap := epb.extensionsWrite()
+	extmap[id] = Extension{enc: b}
 }
 
 // isExtensionField returns true iff the given field number is in an extension range.
@@ -108,8 +199,12 @@ func isExtensionField(pb extendableProto, field int32) bool {
 
 // checkExtensionTypes checks that the given extension is valid for pb.
 func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error {
+	var pbi interface{} = pb
 	// Check the extended type.
-	if a, b := reflect.TypeOf(pb), reflect.TypeOf(extension.ExtendedType); a != b {
+	if ea, ok := pbi.(extensionAdapter); ok {
+		pbi = ea.extendableProtoV1
+	}
+	if a, b := reflect.TypeOf(pbi), reflect.TypeOf(extension.ExtendedType); a != b {
 		return errors.New("proto: bad extended type; " + b.String() + " does not extend " + a.String())
 	}
 	// Check the range.
@@ -155,8 +250,19 @@ func extensionProperties(ed *ExtensionDesc) *Properties {
 	return prop
 }
 
-// encodeExtensionMap encodes any unmarshaled (unencoded) extensions in m.
-func encodeExtensionMap(m map[int32]Extension) error {
+// encode encodes any unmarshaled (unencoded) extensions in e.
+func encodeExtensions(e *XXX_InternalExtensions) error {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return nil // fast path
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	return encodeExtensionsMap(m)
+}
+
+// encode encodes any unmarshaled (unencoded) extensions in e.
+func encodeExtensionsMap(m map[int32]Extension) error {
 	for k, e := range m {
 		if e.value == nil || e.desc == nil {
 			// Extension is only in its encoded form.
@@ -184,7 +290,17 @@ func encodeExtensionMap(m map[int32]Extension) error {
 	return nil
 }
 
-func sizeExtensionMap(m map[int32]Extension) (n int) {
+func extensionsSize(e *XXX_InternalExtensions) (n int) {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return 0
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	return extensionsMapSize(m)
+}
+
+func extensionsMapSize(m map[int32]Extension) (n int) {
 	for _, e := range m {
 		if e.value == nil || e.desc == nil {
 			// Extension is only in its encoded form.
@@ -209,26 +325,51 @@ func sizeExtensionMap(m map[int32]Extension) (n int) {
 }
 
 // HasExtension returns whether the given extension is present in pb.
-func HasExtension(pb extendableProto, extension *ExtensionDesc) bool {
+func HasExtension(pb Message, extension *ExtensionDesc) bool {
 	// TODO: Check types, field numbers, etc.?
-	_, ok := pb.ExtensionMap()[extension.Field]
+	epb, ok := extendable(pb)
+	if !ok {
+		return false
+	}
+	extmap, mu := epb.extensionsRead()
+	if extmap == nil {
+		return false
+	}
+	mu.Lock()
+	_, ok = extmap[extension.Field]
+	mu.Unlock()
 	return ok
 }
 
 // ClearExtension removes the given extension from pb.
-func ClearExtension(pb extendableProto, extension *ExtensionDesc) {
+func ClearExtension(pb Message, extension *ExtensionDesc) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
 	// TODO: Check types, field numbers, etc.?
-	delete(pb.ExtensionMap(), extension.Field)
+	extmap := epb.extensionsWrite()
+	delete(extmap, extension.Field)
 }
 
 // GetExtension parses and returns the given extension of pb.
 // If the extension is not present and has no default value it returns ErrMissingExtension.
-func GetExtension(pb extendableProto, extension *ExtensionDesc) (interface{}, error) {
-	if err := checkExtensionTypes(pb, extension); err != nil {
+func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, errors.New("proto: not an extendable proto")
+	}
+
+	if err := checkExtensionTypes(epb, extension); err != nil {
 		return nil, err
 	}
 
-	emap := pb.ExtensionMap()
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return defaultExtensionValue(extension)
+	}
+	mu.Lock()
+	defer mu.Unlock()
 	e, ok := emap[extension.Field]
 	if !ok {
 		// defaultExtensionValue returns the default value or
@@ -332,10 +473,9 @@ func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
 // GetExtensions returns a slice of the extensions present in pb that are also listed in es.
 // The returned slice has the same length as es; missing extensions will appear as nil elements.
 func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) {
-	epb, ok := pb.(extendableProto)
+	epb, ok := extendable(pb)
 	if !ok {
-		err = errors.New("proto: not an extendable proto")
-		return
+		return nil, errors.New("proto: not an extendable proto")
 	}
 	extensions = make([]interface{}, len(es))
 	for i, e := range es {
@@ -350,9 +490,44 @@ func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, e
 	return
 }
 
+// ExtensionDescs returns a new slice containing pb's extension descriptors, in undefined order.
+// For non-registered extensions, ExtensionDescs returns an incomplete descriptor containing
+// just the Field field, which defines the extension's field number.
+func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, fmt.Errorf("proto: %T is not an extendable proto.Message", pb)
+	}
+	registeredExtensions := RegisteredExtensions(pb)
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return nil, nil
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	extensions := make([]*ExtensionDesc, 0, len(emap))
+	for extid, e := range emap {
+		desc := e.desc
+		if desc == nil {
+			desc = registeredExtensions[extid]
+			if desc == nil {
+				desc = &ExtensionDesc{Field: extid}
+			}
+		}
+
+		extensions = append(extensions, desc)
+	}
+	return extensions, nil
+}
+
 // SetExtension sets the specified extension of pb to the specified value.
-func SetExtension(pb extendableProto, extension *ExtensionDesc, value interface{}) error {
-	if err := checkExtensionTypes(pb, extension); err != nil {
+func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error {
+	epb, ok := extendable(pb)
+	if !ok {
+		return errors.New("proto: not an extendable proto")
+	}
+	if err := checkExtensionTypes(epb, extension); err != nil {
 		return err
 	}
 	typ := reflect.TypeOf(extension.ExtensionType)
@@ -368,10 +543,23 @@ func SetExtension(pb extendableProto, extension *ExtensionDesc, value interface{
 		return fmt.Errorf("proto: SetExtension called with nil value of type %T", value)
 	}
 
-	pb.ExtensionMap()[extension.Field] = Extension{desc: extension, value: value}
+	extmap := epb.extensionsWrite()
+	extmap[extension.Field] = Extension{desc: extension, value: value}
 	return nil
 }
 
+// ClearAllExtensions clears all extensions from pb.
+func ClearAllExtensions(pb Message) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
+	m := epb.extensionsWrite()
+	for k := range m {
+		delete(m, k)
+	}
+}
+
 // A global registry of extensions.
 // The generated code will register the generated descriptors by calling RegisterExtension.
 
diff --git a/vendor/github.com/golang/protobuf/proto/lib.go b/vendor/github.com/golang/protobuf/proto/lib.go
index 0de8f8d..1c22550 100644
--- a/vendor/github.com/golang/protobuf/proto/lib.go
+++ b/vendor/github.com/golang/protobuf/proto/lib.go
@@ -73,7 +73,6 @@ for a protocol buffer variable v:
 When the .proto file specifies `syntax="proto3"`, there are some differences:
 
   - Non-repeated fields of non-message type are values instead of pointers.
-  - Getters are only generated for message and oneof fields.
   - Enum types do not get an Enum method.
 
 The simplest way to describe this is to see an example.
@@ -308,7 +307,7 @@ func GetStats() Stats { return stats }
 // temporary Buffer and are fine for most applications.
 type Buffer struct {
 	buf   []byte // encode/decode byte stream
-	index int    // write point
+	index int    // read point
 
 	// pools of basic types to amortize allocation.
 	bools   []bool
@@ -889,6 +888,10 @@ func isProto3Zero(v reflect.Value) bool {
 	return false
 }
 
+// ProtoPackageIsVersion2 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion2 = true
+
 // ProtoPackageIsVersion1 is referenced from generated protocol buffer files
 // to assert that that code is compatible with this version of the proto package.
 const ProtoPackageIsVersion1 = true
diff --git a/vendor/github.com/golang/protobuf/proto/message_set.go b/vendor/github.com/golang/protobuf/proto/message_set.go
index e25e01e..fd982de 100644
--- a/vendor/github.com/golang/protobuf/proto/message_set.go
+++ b/vendor/github.com/golang/protobuf/proto/message_set.go
@@ -149,9 +149,21 @@ func skipVarint(buf []byte) []byte {
 
 // MarshalMessageSet encodes the extension map represented by m in the message set wire format.
 // It is called by generated Marshal methods on protocol buffer messages with the message_set_wire_format option.
-func MarshalMessageSet(m map[int32]Extension) ([]byte, error) {
-	if err := encodeExtensionMap(m); err != nil {
-		return nil, err
+func MarshalMessageSet(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		if err := encodeExtensions(exts); err != nil {
+			return nil, err
+		}
+		m, _ = exts.extensionsRead()
+	case map[int32]Extension:
+		if err := encodeExtensionsMap(exts); err != nil {
+			return nil, err
+		}
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
 	}
 
 	// Sort extension IDs to provide a deterministic encoding.
@@ -178,7 +190,17 @@ func MarshalMessageSet(m map[int32]Extension) ([]byte, error) {
 
 // UnmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
 // It is called by generated Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
-func UnmarshalMessageSet(buf []byte, m map[int32]Extension) error {
+func UnmarshalMessageSet(buf []byte, exts interface{}) error {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m = exts.extensionsWrite()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return errors.New("proto: not an extension map")
+	}
+
 	ms := new(messageSet)
 	if err := Unmarshal(buf, ms); err != nil {
 		return err
@@ -209,7 +231,16 @@ func UnmarshalMessageSet(buf []byte, m map[int32]Extension) error {
 
 // MarshalMessageSetJSON encodes the extension map represented by m in JSON format.
 // It is called by generated MarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
-func MarshalMessageSetJSON(m map[int32]Extension) ([]byte, error) {
+func MarshalMessageSetJSON(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m, _ = exts.extensionsRead()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
 	var b bytes.Buffer
 	b.WriteByte('{')
 
@@ -252,7 +283,7 @@ func MarshalMessageSetJSON(m map[int32]Extension) ([]byte, error) {
 
 // UnmarshalMessageSetJSON decodes the extension map encoded in buf in JSON format.
 // It is called by generated UnmarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
-func UnmarshalMessageSetJSON(buf []byte, m map[int32]Extension) error {
+func UnmarshalMessageSetJSON(buf []byte, exts interface{}) error {
 	// Common-case fast path.
 	if len(buf) == 0 || bytes.Equal(buf, []byte("{}")) {
 		return nil
diff --git a/vendor/github.com/golang/protobuf/proto/pointer_reflect.go b/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
index 9899141..fb512e2 100644
--- a/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
+++ b/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
@@ -139,6 +139,11 @@ func structPointer_StringSlice(p structPointer, f field) *[]string {
 	return structPointer_ifield(p, f).(*[]string)
 }
 
+// Extensions returns the address of an extension map field in the struct.
+func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
+	return structPointer_ifield(p, f).(*XXX_InternalExtensions)
+}
+
 // ExtMap returns the address of an extension map field in the struct.
 func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
 	return structPointer_ifield(p, f).(*map[int32]Extension)
diff --git a/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go b/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go
index ceece77..6b5567d 100644
--- a/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go
+++ b/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go
@@ -126,6 +126,10 @@ func structPointer_StringSlice(p structPointer, f field) *[]string {
 }
 
 // ExtMap returns the address of an extension map field in the struct.
+func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
+	return (*XXX_InternalExtensions)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
 func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
 	return (*map[int32]Extension)(unsafe.Pointer(uintptr(p) + uintptr(f)))
 }
diff --git a/vendor/github.com/golang/protobuf/proto/properties.go b/vendor/github.com/golang/protobuf/proto/properties.go
index 880eb22..ec2289c 100644
--- a/vendor/github.com/golang/protobuf/proto/properties.go
+++ b/vendor/github.com/golang/protobuf/proto/properties.go
@@ -473,17 +473,13 @@ func (p *Properties) setEncAndDec(typ reflect.Type, f *reflect.StructField, lock
 			p.dec = (*Buffer).dec_slice_int64
 			p.packedDec = (*Buffer).dec_slice_packed_int64
 		case reflect.Uint8:
-			p.enc = (*Buffer).enc_slice_byte
 			p.dec = (*Buffer).dec_slice_byte
-			p.size = size_slice_byte
-			// This is a []byte, which is either a bytes field,
-			// or the value of a map field. In the latter case,
-			// we always encode an empty []byte, so we should not
-			// use the proto3 enc/size funcs.
-			// f == nil iff this is the key/value of a map field.
-			if p.proto3 && f != nil {
+			if p.proto3 {
 				p.enc = (*Buffer).enc_proto3_slice_byte
 				p.size = size_proto3_slice_byte
+			} else {
+				p.enc = (*Buffer).enc_slice_byte
+				p.size = size_slice_byte
 			}
 		case reflect.Float32, reflect.Float64:
 			switch t2.Bits() {
@@ -682,7 +678,8 @@ func getPropertiesLocked(t reflect.Type) *StructProperties {
 	propertiesMap[t] = prop
 
 	// build properties
-	prop.extendable = reflect.PtrTo(t).Implements(extendableProtoType)
+	prop.extendable = reflect.PtrTo(t).Implements(extendableProtoType) ||
+		reflect.PtrTo(t).Implements(extendableProtoV1Type)
 	prop.unrecField = invalidField
 	prop.Prop = make([]*Properties, t.NumField())
 	prop.order = make([]int, t.NumField())
@@ -693,12 +690,15 @@ func getPropertiesLocked(t reflect.Type) *StructProperties {
 		name := f.Name
 		p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false)
 
-		if f.Name == "XXX_extensions" { // special case
+		if f.Name == "XXX_InternalExtensions" { // special case
+			p.enc = (*Buffer).enc_exts
+			p.dec = nil // not needed
+			p.size = size_exts
+		} else if f.Name == "XXX_extensions" { // special case
 			p.enc = (*Buffer).enc_map
 			p.dec = nil // not needed
 			p.size = size_map
-		}
-		if f.Name == "XXX_unrecognized" { // special case
+		} else if f.Name == "XXX_unrecognized" { // special case
 			prop.unrecField = toField(&f)
 		}
 		oneof := f.Tag.Get("protobuf_oneof") // special case
@@ -844,7 +844,29 @@ func RegisterType(x Message, name string) {
 }
 
 // MessageName returns the fully-qualified proto name for the given message type.
-func MessageName(x Message) string { return revProtoTypes[reflect.TypeOf(x)] }
+func MessageName(x Message) string {
+	type xname interface {
+		XXX_MessageName() string
+	}
+	if m, ok := x.(xname); ok {
+		return m.XXX_MessageName()
+	}
+	return revProtoTypes[reflect.TypeOf(x)]
+}
 
 // MessageType returns the message type (pointer to struct) for a named message.
 func MessageType(name string) reflect.Type { return protoTypes[name] }
+
+// A registry of all linked proto files.
+var (
+	protoFiles = make(map[string][]byte) // file name => fileDescriptor
+)
+
+// RegisterFile is called from generated code and maps from the
+// full file name of a .proto file to its compressed FileDescriptorProto.
+func RegisterFile(filename string, fileDescriptor []byte) {
+	protoFiles[filename] = fileDescriptor
+}
+
+// FileDescriptor returns the compressed FileDescriptorProto for a .proto file.
+func FileDescriptor(filename string) []byte { return protoFiles[filename] }
diff --git a/vendor/github.com/golang/protobuf/proto/text.go b/vendor/github.com/golang/protobuf/proto/text.go
index 37c9535..965876b 100644
--- a/vendor/github.com/golang/protobuf/proto/text.go
+++ b/vendor/github.com/golang/protobuf/proto/text.go
@@ -154,7 +154,7 @@ func (w *textWriter) indent() { w.ind++ }
 
 func (w *textWriter) unindent() {
 	if w.ind == 0 {
-		log.Printf("proto: textWriter unindented too far")
+		log.Print("proto: textWriter unindented too far")
 		return
 	}
 	w.ind--
@@ -455,7 +455,7 @@ func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
 
 	// Extensions (the XXX_extensions field).
 	pv := sv.Addr()
-	if pv.Type().Implements(extendableProtoType) {
+	if _, ok := extendable(pv.Interface()); ok {
 		if err := tm.writeExtensions(w, pv); err != nil {
 			return err
 		}
@@ -513,7 +513,7 @@ func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Propert
 	switch v.Kind() {
 	case reflect.Slice:
 		// Should only be a []byte; repeated fields are handled in writeStruct.
-		if err := writeString(w, string(v.Interface().([]byte))); err != nil {
+		if err := writeString(w, string(v.Bytes())); err != nil {
 			return err
 		}
 	case reflect.String:
@@ -689,17 +689,22 @@ func (s int32Slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
 // pv is assumed to be a pointer to a protocol message struct that is extendable.
 func (tm *TextMarshaler) writeExtensions(w *textWriter, pv reflect.Value) error {
 	emap := extensionMaps[pv.Type().Elem()]
-	ep := pv.Interface().(extendableProto)
+	ep, _ := extendable(pv.Interface())
 
 	// Order the extensions by ID.
 	// This isn't strictly necessary, but it will give us
 	// canonical output, which will also make testing easier.
-	m := ep.ExtensionMap()
+	m, mu := ep.extensionsRead()
+	if m == nil {
+		return nil
+	}
+	mu.Lock()
 	ids := make([]int32, 0, len(m))
 	for id := range m {
 		ids = append(ids, id)
 	}
 	sort.Sort(int32Slice(ids))
+	mu.Unlock()
 
 	for _, extNum := range ids {
 		ext := m[extNum]
diff --git a/vendor/github.com/golang/protobuf/proto/text_parser.go b/vendor/github.com/golang/protobuf/proto/text_parser.go
index b5fba5b..5e14513 100644
--- a/vendor/github.com/golang/protobuf/proto/text_parser.go
+++ b/vendor/github.com/golang/protobuf/proto/text_parser.go
@@ -44,6 +44,9 @@ import (
 	"unicode/utf8"
 )
 
+// Error string emitted when deserializing Any and fields are already set
+const anyRepeatedlyUnpacked = "Any message unpacked multiple times, or %q already set"
+
 type ParseError struct {
 	Message string
 	Line    int // 1-based line number
@@ -508,8 +511,16 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 				if err != nil {
 					return p.errorf("failed to marshal message of type %q: %v", messageName, err)
 				}
+				if fieldSet["type_url"] {
+					return p.errorf(anyRepeatedlyUnpacked, "type_url")
+				}
+				if fieldSet["value"] {
+					return p.errorf(anyRepeatedlyUnpacked, "value")
+				}
 				sv.FieldByName("TypeUrl").SetString(extName)
 				sv.FieldByName("Value").SetBytes(b)
+				fieldSet["type_url"] = true
+				fieldSet["value"] = true
 				continue
 			}
 
@@ -550,7 +561,7 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 				}
 				reqFieldErr = err
 			}
-			ep := sv.Addr().Interface().(extendableProto)
+			ep := sv.Addr().Interface().(Message)
 			if !rep {
 				SetExtension(ep, desc, ext.Interface())
 			} else {
@@ -581,7 +592,11 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 			props = oop.Prop
 			nv := reflect.New(oop.Type.Elem())
 			dst = nv.Elem().Field(0)
-			sv.Field(oop.Field).Set(nv)
+			field := sv.Field(oop.Field)
+			if !field.IsNil() {
+				return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, sv.Type().Field(oop.Field).Name)
+			}
+			field.Set(nv)
 		}
 		if !dst.IsValid() {
 			return p.errorf("unknown field name %q in %v", name, st)
@@ -602,8 +617,9 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 
 			// The map entry should be this sequence of tokens:
 			//	< key : KEY value : VALUE >
-			// Technically the "key" and "value" could come in any order,
-			// but in practice they won't.
+			// However, implementations may omit key or value, and technically
+			// we should support them in any order.  See b/28924776 for a time
+			// this went wrong.
 
 			tok := p.next()
 			var terminator string
@@ -615,32 +631,39 @@ func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
 			default:
 				return p.errorf("expected '{' or '<', found %q", tok.value)
 			}
-			if err := p.consumeToken("key"); err != nil {
-				return err
-			}
-			if err := p.consumeToken(":"); err != nil {
-				return err
-			}
-			if err := p.readAny(key, props.mkeyprop); err != nil {
-				return err
-			}
-			if err := p.consumeOptionalSeparator(); err != nil {
-				return err
-			}
-			if err := p.consumeToken("value"); err != nil {
-				return err
-			}
-			if err := p.checkForColon(props.mvalprop, dst.Type().Elem()); err != nil {
-				return err
-			}
-			if err := p.readAny(val, props.mvalprop); err != nil {
-				return err
-			}
-			if err := p.consumeOptionalSeparator(); err != nil {
-				return err
-			}
-			if err := p.consumeToken(terminator); err != nil {
-				return err
+			for {
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == terminator {
+					break
+				}
+				switch tok.value {
+				case "key":
+					if err := p.consumeToken(":"); err != nil {
+						return err
+					}
+					if err := p.readAny(key, props.mkeyprop); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				case "value":
+					if err := p.checkForColon(props.mvalprop, dst.Type().Elem()); err != nil {
+						return err
+					}
+					if err := p.readAny(val, props.mvalprop); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				default:
+					p.back()
+					return p.errorf(`expected "key", "value", or %q, found %q`, terminator, tok.value)
+				}
 			}
 
 			dst.SetMapIndex(key, val)
@@ -773,12 +796,12 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 		fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
 		return p.readAny(fv.Index(fv.Len()-1), props)
 	case reflect.Bool:
-		// Either "true", "false", 1 or 0.
+		// true/1/t/True or false/f/0/False.
 		switch tok.value {
-		case "true", "1":
+		case "true", "1", "t", "True":
 			fv.SetBool(true)
 			return nil
-		case "false", "0":
+		case "false", "0", "f", "False":
 			fv.SetBool(false)
 			return nil
 		}
@@ -842,7 +865,7 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 		return p.readStruct(fv, terminator)
 	case reflect.Uint32:
 		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
-			fv.SetUint(uint64(x))
+			fv.SetUint(x)
 			return nil
 		}
 	case reflect.Uint64:
diff --git a/vendor/vendor.json b/vendor/vendor.json
index 037c981..dabf346 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -15,10 +15,10 @@
 			"revisionTime": "2016-02-29T21:34:45Z"
 		},
 		{
-			"checksumSHA1": "FczzogSoZcKU3h21tCUyHzMsnBY=",
+			"checksumSHA1": "yqF125xVSkmfLpIVGrLlfE05IUk=",
 			"path": "github.com/golang/protobuf/proto",
-			"revision": "7cc19b78d562895b13596ddce7aafb59dd789318",
-			"revisionTime": "2016-04-25T21:53:00Z"
+			"revision": "ab9f9a6dab164b7d1246e0e688b0ab7b94d8553e",
+			"revisionTime": "2017-08-16T00:15:14Z"
 		},
 		{
 			"checksumSHA1": "ZxzYc1JwJ3U6kZbw/KGuPko5lSY=",