[WebKit] Fix for the memory leak

Memory leak was introduced by "DOM traversal optimizations DOM
Core optimizations Prefetch optimization for DOM Tree Traversal"
Cachelist was being mismanaged. Removing it.

Change-Id: I8abb2b6b30b1fbeb931a19be3567c78c3f697d77
Revert "Workaround double blit failure"

This reverts commit 0c274b96c2dfb5a83b12a99f1ca9069378f73bdb.

Change-Id: Iaea6c25cf1aae59e7ce85cd43b028ba9c2e437f0
CRs-fixed: 396141