Revert "Delete paint invalidaiton code in RenderLayerModelObject::styleWillChange."

The revert of https://codereview.chromium.org/360193002
Reason of revert:
The following tests failures
css3/flexbox/repaint-opacity-change.html
fast/repaint/fixed-and-absolute-position-scrolled.html

The actual test expectations look like regression.

http://test-results.appspot.com/dashboards/flakiness_dashboard.html#group=%40ToT%20Blink&tests=css3/flexbox/repaint-opacity-change.html,fast/repaint/fixed-and-absolute-position-scrolled.html

BUG=391036
TBR=chrishtr,pilgrim@chromium.org

Review URL: https://codereview.chromium.org/363283002

git-svn-id: svn://svn.chromium.org/blink/trunk@177460 bbb929c8-8fbe-4397-9dbb-9b2b20218538