Enable Path2D object and some path APIs by default.

Enable following APIs:
  - Path2D Object Constructor & Inteface
  - void fill(Path2D, optional CanvasFillRule);
  - void stroke(Path2D);
  - void clip(Path2D, optional CanvasFillRule);
  - boolean isPointInPath(Path2D, x, y, optional CanvasFillRule);
  - boolean isPointInStroke(Path2D, x, y);

Intent to Ship:
  https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/mhjb3Em8H0A

BUG=159839,330506

Review URL: https://codereview.chromium.org/227583006

git-svn-id: svn://svn.chromium.org/blink/trunk@171302 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[CSS Shapes] shape-outside from image doesn't load properly

Corrected a set of problems related to shape-outside image loading:

- Make RenderImage::imageChanged() call super if there's a shape-outside image, because the shape-outside imageChanged() logic is in RenderBox.

- Added the shape-outside image to appendImagesFromStyle().

- Moved the logic from RenderObject::removeShapeImageClient() from RenderObject::postDestroy() to RenderBox::willDestroy() because it's simpler that way.


BUG=360668

Review URL: https://codereview.chromium.org/226203010

git-svn-id: svn://svn.chromium.org/blink/trunk@171303 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Auto-rebaseline for r171287

http://src.chromium.org/viewvc/blink?view=revision&revision=171287

BUG=360571
TBR=fs@opera.com

Review URL: https://codereview.chromium.org/233863002

git-svn-id: svn://svn.chromium.org/blink/trunk@171304 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove unused WebMessagePortChannel::entangle() method

Chromium-side:
https://codereview.chromium.org/232623002/

BUG=361001

Review URL: https://codereview.chromium.org/232563004

git-svn-id: svn://svn.chromium.org/blink/trunk@171305 bbb929c8-8fbe-4397-9dbb-9b2b20218538