[Chromium] Add GL_CHROMIUM_async_pixel_transfers extension support.
https://bugs.webkit.org/show_bug.cgi?id=103995

Patch by David Reveman <reveman@chromium.org> on 2012-12-06
Reviewed by Kenneth Russell.

Add asyncTexImage2DCHROMIUM and asyncTexSubImage2DCHROMIUM to
WebGraphicsContext3D.h.

* chromium/public/WebGraphicsContext3D.h:
(WebGraphicsContext3D):
(WebKit::WebGraphicsContext3D::asyncTexImage2DCHROMIUM):
(WebKit::WebGraphicsContext3D::asyncTexSubImage2DCHROMIUM):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk/Source/Platform/chromium/public@136858 268f45cc-cd09-0410-ab3c-d52691b4dbfc