element: add gst_element_class_add_static_pad_template()

Pretty much every single element does

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&some_templ));

which is both confusing and unnecessary. We might just
as well add a function to do that in one step.

https://bugzilla.gnome.org/show_bug.cgi?id=762778

docs/gst/gstreamer-sections.txt

@@ -827,6 +827,7 @@ GST_ELEMENT_METADATA_LONGNAME
 
 <SUBSECTION element-construction>
 gst_element_class_add_pad_template
+gst_element_class_add_static_pad_template
 gst_element_class_get_pad_template
 gst_element_class_get_pad_template_list
 gst_element_class_set_metadata

gst/gstelement.c

@@ -1229,6 +1229,26 @@ gst_element_class_add_pad_template (GstElementClass * klass,
   klass->numpadtemplates++;
 }
 
+/**
+ * gst_element_class_add_static_pad_template:
+ * @klass: the #GstElementClass to add the pad template to.
+ * @templ: #GstStaticPadTemplate to add as pad template to the element class.
+ *
+ * Adds a pad template to an element class based on the static pad template
+ * @templ. This is mainly used in the _class_init functions of element
+ * implementations. If a pad template with the same name already exists,
+ * the old one is replaced by the new one.
+ *
+ * Since: 1.8
+ */
+void
+gst_element_class_add_static_pad_template (GstElementClass * klass,
+    GstStaticPadTemplate * static_templ)
+{
+  gst_element_class_add_pad_template (klass,
+      gst_static_pad_template_get (static_templ));
+}
+
 /**
  * gst_element_class_add_metadata:
  * @klass: class to set metadata for

gst/gstelement.h

@@ -663,6 +663,9 @@ struct _GstElementClass
 
 /* element class pad templates */
 void                    gst_element_class_add_pad_template      (GstElementClass *klass, GstPadTemplate *templ);
+
+void                    gst_element_class_add_static_pad_template (GstElementClass *klass, GstStaticPadTemplate *static_templ);
+
 GstPadTemplate*         gst_element_class_get_pad_template      (GstElementClass *element_class, const gchar *name);
 GList*                  gst_element_class_get_pad_template_list (GstElementClass *element_class);
 

win32/common/libgstreamer.def

@@ -480,6 +480,7 @@ EXPORTS
 	gst_element_class_add_metadata
 	gst_element_class_add_pad_template
 	gst_element_class_add_static_metadata
+	gst_element_class_add_static_pad_template
 	gst_element_class_get_metadata
 	gst_element_class_get_pad_template
 	gst_element_class_get_pad_template_list