Revert 162056 "RenderBlockFlow::nextFloatLogicalBottomBelow shou..."

Cause http://www.theverge.com/2013/3/5/4061684/inside-ted-the-smartest-bubble-in-the-world not to finish loading

See crbug.com/320032 for reproducing steps.

Apparently the code path in this CL is not covered by any unittest/layout_tests

Before trying to land it again, please figure out a way to test it first.

This caused the blink tree to be closed for three hours today.

> RenderBlockFlow::nextFloatLogicalBottomBelow should not use ShapeOutsideFloatOffsetMode
> 
> Rewrite nextFloatLogicalBottomBelow to use the placed floats tree for the
> search and to not need ShapeOutsideFloatOffsetMode anymore. This moves almost
> all of the logic into FloatingObjects, making a small reduction in the amount
> that RenderBlockFlow needs to know about the implementation of FloatingObjects.
> 
> In addition, change ComputeFloatOffsetAdapter to take in LayoutUnits and
> roundToInt itself so that all of it's callers can be simplified.
> 
> Review URL: https://codereview.chromium.org/68123004

TBR=bjonesbe@adobe.com

Review URL: https://codereview.chromium.org/67883008

git-svn-id: svn://svn.chromium.org/blink/trunk@162145 bbb929c8-8fbe-4397-9dbb-9b2b20218538