Invalidate the frame view when changing the background image of the document or body.

To do this, add a method to request full paint invalidation on FrameView. This also requires moving the full invalidation code into invalidateTreeIfNeeded() instead of layout(), since otherwise the invalidation requested will not always happen if layout does not occur.

In any case, invalidation should be in invalidateTreeIfNeeded(), not layout().

BUG=425872

Review URL: https://codereview.chromium.org/683373002

git-svn-id: svn://svn.chromium.org/blink/trunk@184836 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove some EME tests from Oilpan failing list

These tests appear to be running normally now on the Mac Oilpan clients.

BUG=370586
TEST=flakiness dashboard all green for these tests

Review URL: https://codereview.chromium.org/685983006

git-svn-id: svn://svn.chromium.org/blink/trunk@184837 bbb929c8-8fbe-4397-9dbb-9b2b20218538