DOM children of a region must not be rendered as children of the region, but can be collected in flow threads.

Ported and improved from https://bugs.webkit.org/show_bug.cgi?id=74144

BUG=228566

Review URL: https://chromiumcodereview.appspot.com/18080016

git-svn-id: svn://svn.chromium.org/blink/trunk@153439 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add trace for text auto sizing

Locally added trace showed that text auto sizing is a big factor
in layout performance. It would be useful to show the time used for
text auto sizing during layout.

BUG=none

Review URL: https://chromiumcodereview.appspot.com/18401003

git-svn-id: svn://svn.chromium.org/blink/trunk@153440 bbb929c8-8fbe-4397-9dbb-9b2b20218538
We should not need to reach for Page when applying styles.

There was some consulting of the Page::deviceScaleFactor while mapping CSSPropertyID to StyleImage, but it isn't necessary: the deviceScaleFactor stays unchanged for the duration of element style resolve.

R=eae, eseidel
BUG=237268

Review URL: https://chromiumcodereview.appspot.com/18561002

git-svn-id: svn://svn.chromium.org/blink/trunk@153441 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Unofficial gardening. Mark some fast/canvas tests as Slow rather than Pass Timeout.

BUG=248415,234758,237270,243243,244004
TBR=crogers

Review URL: https://codereview.chromium.org/18559007

git-svn-id: svn://svn.chromium.org/blink/trunk@153442 bbb929c8-8fbe-4397-9dbb-9b2b20218538
More rebaseline after "Remove calls to updateMarqueePosition from RenderLayer"

Remove a bad baseline for lion that was making the bot red. The other removal
was done by garden-o-matic to optimize the TEXT baselines.

TBR=leviw@chromium.org

Review URL: https://codereview.chromium.org/18205005

git-svn-id: svn://svn.chromium.org/blink/trunk@153443 bbb929c8-8fbe-4397-9dbb-9b2b20218538