Don't use stale compositing state in LocalFrame::nodeImage

Don't use stale compositing state in LocalFrame::nodeImage

This patch fixes a compositor chicken and egg bug in
LocalFrame::nodeImage where stale compositor state was read through
setBaseBackgroundColor. An updateLayoutAndStyleForPainting call has
been moved before setBaseBackgroundColor in nodeImage.

Additionally, two unnecessary protector RefPtrs have been removed
because the callers already ref'ed the objects. The Node RefPtr is
ref'ed by Clipboard, the nodeImage() caller. The LocalFrame RefPtr
is ref'ed by DragController::doSystemDrag.

As a cleanup, LocalFrame::nodeImage has been changed to
take a reference since the node cannot be null.

BUG=354373
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=170135

[abarth-chromium, 2014-03-27 04:11:58]

lgtm

[pdr., 2014-03-27 04:12:53]

The CQ bit was checked by pdr@chromium.org

[commit-bot: I haz the power, 2014-03-27 04:12:56]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/pdr@chromium.org/214053003/1

[commit-bot: I haz the power, 2014-03-27 04:42:30]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-03-27 04:42:31]

Try jobs failed on following builders:
  tryserver.blink on mac_blink_rel

[pdr., 2014-03-27 04:44:36]

The CQ bit was checked by pdr@chromium.org

[commit-bot: I haz the power, 2014-03-27 04:44:39]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/pdr@chromium.org/214053003/1

[commit-bot: I haz the power, 2014-03-27 05:17:13]

Change committed as 170135