Attempt to clean up requiresLayoutToDetermineWidth to be more clear

Attempt to clean up requiresLayoutToDetermineWidth to be more clear

This code is brittle, and definitely wrong in some cases
but hopefully this is more clear now.

We need to find a path to making this more maintainable.  Clearly
this win is worth this complexity, we just need to figure out
how to not have more bad regressions from this.

BUG=247470
R=jchaffraix@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=158551

[Julien - ping for review, 2013-09-30 16:28:06]

lgtm

https://codereview.chromium.org/25048006/diff/9001/Source/core/rendering/Rend...
File Source/core/rendering/RenderBox.cpp (right):

https://codereview.chromium.org/25048006/diff/9001/Source/core/rendering/Rend...
Source/core/rendering/RenderBox.cpp:413: // FIXME: There are likely many
subclasses of RenderBlockFlow which
Maybe also classes outside RenderBlockFlow?

https://codereview.chromium.org/25048006/diff/9001/Source/core/rendering/Rend...
Source/core/rendering/RenderBox.cpp:420: // Table Layout controls cell size,
width is ignored.
width is not ignored when doing a table layout. On the contrary, it is used to
determine the cell's width. What is important is that the table layout algorithm
can override the computed width, which is why we have to run layout.

https://codereview.chromium.org/25048006/diff/9001/Source/core/rendering/Rend...
Source/core/rendering/RenderBox.cpp:2100: itemMarker->layout();
layoutIfNeeded()?

[eseidel, 2013-09-30 23:20:31]

Committed patchset #2 manually as r158551 (presubmit successful).