[gobject] Fix a few warnings

Part of https://github.com/behdad/harfbuzz/issues/277

src/hb-buffer.cc

@@ -52,7 +52,7 @@
  *
  * Checks the equality of two #hb_segment_properties_t's.
  *
- * Return value: (transfer full):
+ * Return value:
  * %true if all properties of @a equal those of @b, false otherwise.
  *
  * Since: 0.9.7

src/hb-gobject-structs.h

@@ -41,30 +41,40 @@ HB_BEGIN_DECLS
 /* Object types */
 
 /**
+ * hb_gobject_blob_get_type:
+ *
  * Since: 0.9.2
  **/
 HB_EXTERN GType hb_gobject_blob_get_type (void);
 #define HB_GOBJECT_TYPE_BLOB (hb_gobject_blob_get_type ())
 
 /**
+ * hb_gobject_buffer_get_type:
+ *
  * Since: 0.9.2
  **/
 HB_EXTERN GType hb_gobject_buffer_get_type (void);
 #define HB_GOBJECT_TYPE_BUFFER (hb_gobject_buffer_get_type ())
 
 /**
+ * hb_gobject_face_get_type:
+ *
  * Since: 0.9.2
  **/
 HB_EXTERN GType hb_gobject_face_get_type (void);
 #define HB_GOBJECT_TYPE_FACE (hb_gobject_face_get_type ())
 
 /**
+ * hb_gobject_font_get_type:
+ *
  * Since: 0.9.2
  **/
 HB_EXTERN GType hb_gobject_font_get_type (void);
 #define HB_GOBJECT_TYPE_FONT (hb_gobject_font_get_type ())
 
 /**
+ * hb_gobject_font_funcs_get_type:
+ *
  * Since: 0.9.2
  **/
 HB_EXTERN GType hb_gobject_font_funcs_get_type (void);
@@ -77,6 +87,8 @@ HB_EXTERN GType hb_gobject_shape_plan_get_type (void);
 #define HB_GOBJECT_TYPE_SHAPE_PLAN (hb_gobject_shape_plan_get_type ())
 
 /**
+ * hb_gobject_unicode_funcs_get_type:
+ *
  * Since: 0.9.2
  **/
 HB_EXTERN GType hb_gobject_unicode_funcs_get_type (void);

src/hb-shape.cc

@@ -394,8 +394,6 @@ hb_shape_full (hb_font_t          *font,
  * positioned glyphs. If @features is not %NULL, it will be used to control the
  * features applied during shaping.
  *
- * Return value: %FALSE if all shapers failed, %TRUE otherwise
- *
  * Since: 0.9.2
  **/
 void

src/hb-unicode.h

@@ -449,33 +449,18 @@ HB_EXTERN hb_script_t
 hb_unicode_script (hb_unicode_funcs_t *ufuncs,
 		   hb_codepoint_t unicode);
 
-/**
- * hb_unicode_compose:
- *
- * Since: 0.9.2
- **/
 HB_EXTERN hb_bool_t
 hb_unicode_compose (hb_unicode_funcs_t *ufuncs,
 		    hb_codepoint_t      a,
 		    hb_codepoint_t      b,
 		    hb_codepoint_t     *ab);
 
-/**
- * hb_unicode_decompose:
- *
- * Since: 0.9.2
- **/
 HB_EXTERN hb_bool_t
 hb_unicode_decompose (hb_unicode_funcs_t *ufuncs,
 		      hb_codepoint_t      ab,
 		      hb_codepoint_t     *a,
 		      hb_codepoint_t     *b);
 
-/**
- * hb_unicode_decompose_compatibility:
- *
- * Since: 0.9.2
- **/
 HB_EXTERN unsigned int
 hb_unicode_decompose_compatibility (hb_unicode_funcs_t *ufuncs,
 				    hb_codepoint_t      u,