Timeline: fix expansion arrow appearing on rows with no visible children

We used to check TimelinePresentationRecord.expandable(), but it was accidrently replaced
with hasPresentationChildren(), which is not the same now, since we keep hidden records
in the presentation model.

R=pfeldman@chromium.org

Review URL: https://codereview.chromium.org/201823003

git-svn-id: svn://svn.chromium.org/blink/trunk@169620 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Use new Traversal<*Element> API in svg code for clarity

Use new Traversal<*Element> API in svg code for clarity. It results in shorter /
simpler code. It also makes it clearer what type of Element we are actually
interested in.

R=
BUG=346733

Review URL: https://codereview.chromium.org/205983004

git-svn-id: svn://svn.chromium.org/blink/trunk@169621 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Oilpan: Prepare to move AbstractSQLStatementBackend and SQLStatementBackend to Oilpan heap.

They are ThreadSafeRefCounted because an object is created in a context thread,
is enqueued into a SQLTransactionBackend, the SQLTransactionBackend is moved to
a database thread, then the database thread takes a SQLStatementBackend in the
queue.
We don't need to care about it in Oilpan. SQLTransactionBackend is correctly
transferred with CrossThreadPersistent.

BUG=347902

Review URL: https://codereview.chromium.org/205823002

git-svn-id: svn://svn.chromium.org/blink/trunk@169622 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Oilpan: Prepare to move InspectorDatabaseResource to Oilpan heap.

BUG=347902

Review URL: https://codereview.chromium.org/205853002

git-svn-id: svn://svn.chromium.org/blink/trunk@169623 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Fix pixel snapping of clipLayers and their descendants

Hopefully the last in a line of compositing sub-pixel
patches. This correctly pixel snaps the clipping layer
used by composited layers with overflow: clip and
accumulates it into their children.

BUG=347521

Review URL: https://codereview.chromium.org/205213006

git-svn-id: svn://svn.chromium.org/blink/trunk@169624 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Auto-rebaseline for r169605

http://src.chromium.org/viewvc/blink?view=revision&revision=169605

BUG=354165
TBR=eae@chromium.org

Review URL: https://codereview.chromium.org/196243008

git-svn-id: svn://svn.chromium.org/blink/trunk@169625 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Web Animations API: Fix KeyframeEffectModel::PropertySpecificKeyframeGroup::addSyntheticKeyframeIfRequired

Synthetic Keyframes:
For each property declared in a KeyframeEffectModel, addSyntheticKeyframeIfRequired adds
a property specific keyframe at offset: 0 if none exists. Similarly, it adds a keyframe
at offset: 1 if required.

The synthetic keyframes have compositeOperation add, and a neutral value for the property.

Partial Keyframes:
Previously, if an animation was constructed with a partial keyframe (a keyframe list with no 
keyframe at offset zero or no keyframe at offset one for any of the properties it declares) 
the renderer would crash. 

This change detects partial keyframes and throws a NotSupportedError in the JavaScript.

Review URL: https://codereview.chromium.org/203463009

git-svn-id: svn://svn.chromium.org/blink/trunk@169626 bbb929c8-8fbe-4397-9dbb-9b2b20218538