Crash in RenderBlock::addChildIgnoringAnonymousColumnBlocks.

Crash in RenderBlock::addChildIgnoringAnonymousColumnBlocks.
https://bugs.webkit.org/show_bug.cgi?id=79043

Reviewed by Julien Chaffraix.

Source/WebCore:

Tests: fast/runin/runin-div-before-child.html
       fast/runin/runin-table-before-child.html

* rendering/RenderBlock.cpp:
(WebCore::RenderBlock::addChildIgnoringAnonymousColumnBlocks): handle
the case of run-in elements and strengthen code to handle cases where
beforeChild is incorrectly set.
* rendering/RenderObject.h: remove anonymousContainer function since
the new logic in RenderBlock does not need it.

LayoutTests:

* fast/runin/runin-div-before-child-expected.png: Added.
* fast/runin/runin-div-before-child-expected.txt: Added.
* fast/runin/runin-div-before-child.html: Added.
* fast/runin/runin-table-before-child-expected.png: Added.
* fast/runin/runin-table-before-child-expected.txt: Added.
* fast/runin/runin-table-before-child.html: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@108606 268f45cc-cd09-0410-ab3c-d52691b4dbfc