The default render object layout implementation is dead code

The default render object layout implementation is dead code

While trying to refactor the render tree layout to be non-recursive I discovered
that the default render object layout implementation is dead code.  First, I put
an assert to find a layouttest that exercised it, but could not find any.  Next,
I made the method pure virtual to see what subclasses used the default impl and
found to my surprise that none do!

BUG=331879
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=164846

[atreat, 2014-01-10 01:29:56]

This is pretty surprising I think, but it is dead code.  The two bot failures do
not look related and the fact that it compiles on all bots proves that no
RenderObject subclass uses the default impl of RenderObject::layout

[esprehn, 2014-01-10 02:15:53]

lgtm, this is awesome.

[Inactive, 2014-01-10 02:45:31]

lgtm

[commit-bot: I haz the power, 2014-01-10 02:45:44]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/adam.treat@samsung.com/132703002/1

[commit-bot: I haz the power, 2014-01-10 06:21:51]

Change committed as 164846