[463/906] Add some more G_{BEGIN,END}_DECLS to public headers

https://bugzilla.gnome.org/show_bug.cgi?id=637260

gst-libs/gst/gl/gstglbuffer.h

@@ -27,6 +27,8 @@
 
 #include "gstgldisplay.h"
 
+G_BEGIN_DECLS
+
 typedef struct _GstGLBuffer GstGLBuffer;
 
 #define GST_TYPE_GL_BUFFER (gst_gl_buffer_get_type())
@@ -66,5 +68,6 @@ gboolean gst_gl_buffer_parse_caps (GstCaps* caps, gint* width, gint* height);
   "pixel-aspect-ratio=(fraction)1/1," \
   "framerate=(fraction)[0/1,100/1]"
 
-#endif
+G_END_DECLS
 
+#endif /* _GST_GL_BUFFER_H_ */

gst-libs/gst/gl/gstgldisplay.h

@@ -28,6 +28,8 @@
 #include "gstglwindow.h"
 #include "gstglshader.h"
 
+G_BEGIN_DECLS
+
 #define GST_TYPE_GL_DISPLAY			\
   (gst_gl_display_get_type())
 #define GST_GL_DISPLAY(obj)						\
@@ -290,4 +292,6 @@ void gst_gl_display_set_client_data (GstGLDisplay * display, gpointer data);
 gulong gst_gl_display_get_internal_gl_context (GstGLDisplay * display);
 void gst_gl_display_activate_gl_context (GstGLDisplay * display, gboolean activate);
 
-#endif
+G_END_DECLS
+
+#endif /* __GST_GL_H__ */

gst-libs/gst/gl/gstgles2.h

@@ -23,6 +23,8 @@
 #ifndef __GST_GL_ES2__
 #define __GST_GL_ES2__
 
+G_BEGIN_DECLS
+
 /* GLEW */
 
 #define GLEW_OK 0
@@ -112,4 +114,6 @@
 #define GL_TEXTURE_ENV 0
 #define GL_TEXTURE_ENV_MODE 0
 
+G_END_DECLS
+
 #endif /* __GST_GL_ES2__ */