commit 379688948f2ad35196a893225dec2ea7efa46a17
author trchen@chromium.org <trchen@chromium.org@bbb929c8-8fbe-4397-9dbb-9b2b20218538> Sat Jun 14 01:23:47 2014
committer trchen@chromium.org <trchen@chromium.org@bbb929c8-8fbe-4397-9dbb-9b2b20218538> Sat Jun 14 01:23:47 2014
tree 35179842a43eee4b80ade31e0325955a8bc86400
parent 0e848592f49acaca568e4c8a8697b363c68eea6c

Layout overflow from transforms should update frame scrollbars

This CL implements frame scrollbar update for the overflow recalc fast path
without invoking layout. This fast path first determines whether scrollbars
need to be created or removed (in that case, a layout will be needed), and
update scrollbars without layout if possible.

TEST=fast/transforms/transform-update-frame-overflow.html
BUG=354167

Review URL: https://codereview.chromium.org/328023002

git-svn-id: svn://svn.chromium.org/blink/trunk@176143 bbb929c8-8fbe-4397-9dbb-9b2b20218538