CSS Animations: Add interpolation test for perspective-origin

This exposes some inaccuracies in the existing implementation. Web Animations behavior matches Gecko.

Review URL: https://chromiumcodereview.appspot.com/23811010

git-svn-id: svn://svn.chromium.org/blink/trunk@157741 bbb929c8-8fbe-4397-9dbb-9b2b20218538
CSS Animations: Add support for testing interpolation on SVG elements

Review URL: https://chromiumcodereview.appspot.com/23591042

git-svn-id: svn://svn.chromium.org/blink/trunk@157742 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add toSVGStyleElement(), and use it.

This function has type checking assertions for helping to find bad-cast bugs.

BUG=N/A

Review URL: https://chromiumcodereview.appspot.com/24061004

git-svn-id: svn://svn.chromium.org/blink/trunk@157743 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Move Pause on Exception button to sidebar.

BUG=143952

* Moved the Pause on Exception button to the sidebar.
* Remove from status bar items.
* Quick simplification.

Review URL: https://chromiumcodereview.appspot.com/23685008

git-svn-id: svn://svn.chromium.org/blink/trunk@157744 bbb929c8-8fbe-4397-9dbb-9b2b20218538