Set an error if we encounter properties without values set (#451303,

* gtk/gtkbuilder.h (enum): 
    * gtk/gtkbuilderparser.c (end_element): 
    * tests/buildertest.c (test_parser): 
    Set an error if we encounter properties without values set
    (#451303, Philip Withnall)


svn path=/trunk/; revision=18252

gtk/gtkbuilder.h

@@ -43,7 +43,8 @@ typedef enum
   GTK_BUILDER_ERROR_UNHANDLED_TAG,
   GTK_BUILDER_ERROR_MISSING_ATTRIBUTE,
   GTK_BUILDER_ERROR_INVALID_ATTRIBUTE,
-  GTK_BUILDER_ERROR_INVALID_TAG
+  GTK_BUILDER_ERROR_INVALID_TAG,
+  GTK_BUILDER_ERROR_MISSING_PROPERTY_VALUE
 } GtkBuilderError;
 
 GQuark gtk_builder_error_quark (void);