https://bugs.webkit.org/show_bug.cgi?id=78059

Reviewed by Adam Barth.

CodeGeneratorGObject.pm does not support custom attributes.
We can skip generating code for attributes with [Custom].
The change would make sense, since CodeGeneratorGObject.pm already
skips attributes with [CustomGetter] or [CustomSetter].

Test: bindings/scripts/test/TestObj.idl

* bindings/scripts/CodeGeneratorGObject.pm:
(SkipAttribute):
* bindings/scripts/test/GObject/WebKitDOMTestObj.cpp:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@107034 268f45cc-cd09-0410-ab3c-d52691b4dbfc