Remove illegal compositing queries in RenderObject::adjustStyleDifference

This replaces calls to RenderLayer::hasDirectReasonsForCompositing in
RenderObject::adjustStyleDifference with calls to
RenderLayer::styleDeterminedCompositingReasons.

This also removes hasDirectReasonsForCompositing altogether, as it
no longer has any callers.

Review URL: https://codereview.chromium.org/327593002

git-svn-id: svn://svn.chromium.org/blink/trunk@175842 bbb929c8-8fbe-4397-9dbb-9b2b20218538