[Cleanup] Follow Up of Pinch/Zoom Infrastucture & Plumbing CL

Follow up of Pinch/Zoom Infrastructure & Plumbing CL to remove methods
related to max scroll offset and making clip layer methods pure virtual.

This CL is followup on https://codereview.chromium.org/23983047.

BUG=148816

Review URL: https://codereview.chromium.org/139923006

git-svn-id: svn://svn.chromium.org/blink/trunk@166454 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: EventTarget arguments

12 => 11

BUG=239771
R=haraken
NOTRY=true

Review URL: https://codereview.chromium.org/155523003

git-svn-id: svn://svn.chromium.org/blink/trunk@166455 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: [ReflectOnly]

Python side to:
Support IDL attributes limited to only known values.
https://codereview.chromium.org/124763002/

BUG=239771
R=haraken
NOTRY=true

Review URL: https://codereview.chromium.org/145773004

git-svn-id: svn://svn.chromium.org/blink/trunk@166456 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Web Animations: Add bindings for Player

This patch adds the remaining bindings for Player, aside from timeline
since we haven't yet added the DocumentTimeline bindings. Since most
of the functionality of Player is unit tested, the added test only
does sanity checks for the main parts of the interface. Also this makes
the element.animate test stop using internals and instead use the added
bindings.

Spec: http://dev.w3.org/fxtf/web-animations/#idl-def-Player

BUG=334926

Review URL: https://codereview.chromium.org/152493002

git-svn-id: svn://svn.chromium.org/blink/trunk@166457 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: [ReflectMissing], [ReflectInvalid]

Python side to:
Support missing and invalid defaults for reflected attributes.
https://codereview.chromium.org/98033003/

Followup to:
IDL compiler: [ReflectOnly]
https://codereview.chromium.org/145773004/

Remaining: 11 => 9

BUG=239771
R=haraken
NOTRY=true

Review URL: https://codereview.chromium.org/152043003

git-svn-id: svn://svn.chromium.org/blink/trunk@166458 bbb929c8-8fbe-4397-9dbb-9b2b20218538