Merge 143318

Merge 143318
> [Text Autosizing] Combine narrow descendants of a cluster into groups that should be autosized with the same multiplier.
> https://bugs.webkit.org/show_bug.cgi?id=109825
> 
> Source/WebCore:
> 
> Enhancement of the approach introduced in https://bugs.webkit.org/show_bug.cgi?id=109573.
> Instead of using the same text size multiplier for all narrow descendants of any autosizing
> cluster, group the descendants by how much narrower they are than the cluster's
> |blockContainingAllText| and process each group separately with a different multiplier for
> each one.
> For example, we want nested comments on the page to be autosized as a group but separately
> from a sidebar on the same page.
> 
> Patch by Anton Vayvod <avayvod@chromium.org>; on 2013-02-19
> Reviewed by Kenneth Rohde Christiansen.
> 
> Updated the existing test to verify the patch.
> 
> * rendering/TextAutosizer.cpp:
> (WebCore::TextAutosizer::processClusterInternal):
> 
>     Splits the narrow descendants of the autosizing cluster into groups before processing
>     each group individually.
> 
> (WebCore::TextAutosizer::getNarrowDescendantsGroupedByWidth):
> 
>     Sorts the narrow descendants of the given cluster into groups, combining them by the
>     difference between their content widths. If sorted by width, two consecutive nodes
>     belong to the same group if their width difference is no greater than 100 CSS units.
> 
> * rendering/TextAutosizer.h:
> 
>     New method definitions.
> 
> LayoutTests:
> 
> Verify that narrow descendants are grouped and autosized separately according to the
> difference between the descendant's width and the width of its enclosing cluster's
> |blockContainingAllText|.
> 
> Patch by Anton Vayvod <avayvod@chromium.org>; on 2013-02-19
> Reviewed by Kenneth Rohde Christiansen.
> 
> * fast/text-autosizing/narrow-descendants-combined-expected.html:
> * fast/text-autosizing/narrow-descendants-combined.html:

TBR=commit-queue@webkit.org
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=143932

[Peter Beverloo, 2013-02-25 16:54:37]

Committed patchset #1 manually as r143932.