Revert "[WK2] calculate tiledBackingStoreVisibleRect including animation trajectory."

Revert "[WK2] calculate tiledBackingStoreVisibleRect including animation trajectory."

This reverts commit df16f73a1980a8f36435dcf12df316e9d579032c.

[Title] Revert "[WK2] calculate tiledBackingStoreVisibleRect including animation trajectory."
[Issues] N/A
[Problem] -webkit-transition uses too much memory.
[Solution] Revert "[WK2] calculate tiledBackingStoreVisibleRect including animation trajectory."

Conflicts:
	Source/WebKit2/WebProcess/WebPage/LayerTreeCoordinator/WebGraphicsLayer.cpp

Change-Id: I1c87f0bd2f9174f0e18e8f0003bab570dc6afd3f