Revert 228751 "Implement features in NativeViewHostAura for scro..."

> Implement features in NativeViewHostAura for scroll end effect
> 
> This CL enables the fast resize path on Aura by implementing
> NativeViewHostAura::InstallClip. It also adds the concept of gravity to
> the fast resize state to control the positioning of the clip relative
> to the contents. Gravity is implemented for Aura only in this CL and
> ignored in other implementations.
> 
> BUG=151356
> BUG=282463
> TEST=Confirmed the fast path and gravity works in conjunction with
>      scroll end effect CL. Added and updated unit tests.
> 
> Review URL: https://codereview.chromium.org/24299004

TBR=rharrison@chromium.org

Review URL: https://codereview.chromium.org/27566002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228961 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228961