Revert r154731 "Move presentation attribute style code out of Element.cpp" I suspect it breaks WebFrameCSSCallbackTest.CatchesAttributeChange. Will re-land if that is not the case.

Review URL: https://codereview.chromium.org/28303002

git-svn-id: svn://svn.chromium.org/blink/trunk@159934 bbb929c8-8fbe-4397-9dbb-9b2b20218538