Remove unused method declarations from Notification.h

They don't have implementation and are referred by nothing.

Also move finalize() to private which is not referred by any other class.

BUG=none

Review URL: https://codereview.chromium.org/68253008

git-svn-id: svn://svn.chromium.org/blink/trunk@161763 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Web Animations: Add toKeyframeAnimationEffect

Review URL: https://codereview.chromium.org/69713002

git-svn-id: svn://svn.chromium.org/blink/trunk@161764 bbb929c8-8fbe-4397-9dbb-9b2b20218538