[chromium] Remove the WebCompositorSupport virtual methods from the base class
https://bugs.webkit.org/show_bug.cgi?id=102153

Reviewed by James Robinson.

These methods have now been removed from WebCompositorSupportImpl in
chromium and should be removed from the base class. Everything is
going through WebLayerTreeSettings now.

* chromium/public/WebCompositorSupport.h:


git-svn-id: https://svn.webkit.org/repository/webkit/trunk/Source/Platform/chromium/public@135216 268f45cc-cd09-0410-ab3c-d52691b4dbfc