RenderLayerBacking should have RenderLayer& backpointer.
<https://webkit.org/b/122731>

Reviewed by Anders Carlsson.

RenderLayerBacking is always owned by a RenderLayer and so should
store its backpointer in a reference.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157378 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Unreviewed GTK gardening.

* platform/gtk-wk2/TestExpectations:
Add bug number to the failing animation tests.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157379 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Roll deps^H^H^H^HChangeLogs.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157380 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Rewrite Document::body and Document::head in modern style, way clearer and shorter
https://bugs.webkit.org/show_bug.cgi?id=122717

Reviewed by Andreas Kling.

* dom/Document.cpp:
(WebCore::Document::body): Use iterator to make this way easier to read.
(WebCore::Document::head): Ditto.

* html/HTMLTagNames.in: Added generateTypeHelpers for body and head.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157381 268f45cc-cd09-0410-ab3c-d52691b4dbfc