Remove assert guarding against providing keyframes with 'add' composite.
This is now tested by KeyframeEffectModelBase::isReplaceOnly(), which
means that API-provided keyframes with add compositing throw an exception
rather than crashing.

Review URL: https://codereview.chromium.org/250843006

git-svn-id: svn://svn.chromium.org/blink/trunk@172850 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Oilpan: Fix build now that AnimationEffect is exposed to JavaScript.

TBR=haraken@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/260083009

git-svn-id: svn://svn.chromium.org/blink/trunk@172851 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Layout bindings calls back onto JS frames.

BUG=363976

Review URL: https://codereview.chromium.org/251133002

git-svn-id: svn://svn.chromium.org/blink/trunk@172852 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Cleanup: Replace adjustForColumns() / offsetForColumns() with columnOffset().

Most of the former adjustForColumns() call sites now look simpler,
since they call a method that returns the offset instead of using
pass-by-reference.

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/259993006

git-svn-id: svn://svn.chromium.org/blink/trunk@172853 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Sync VTTCue.align/vertical with spec

http://dev.w3.org/html5/webvtt/#vttcue-interface

The tests have already been fixed in web-platform-tests:
https://github.com/w3c/web-platform-tests/commit/5e4f41f421cc87e8bdd154043e20531cc79ec76d

BUG= 367555

Review URL: https://codereview.chromium.org/254833003

git-svn-id: svn://svn.chromium.org/blink/trunk@172854 bbb929c8-8fbe-4397-9dbb-9b2b20218538