Speculative fix for crash due to stale GraphicsLayer configuration

This CL:

https://chromium-review.googlesource.com/c/chromium/src/+/1600078

... inadvertently changed the behavior of
LocalFrameView::CrossOriginStatusChanged -- specifically, in the
case where an iframe becomes cross-origin and that causes it to
become throttled.

BUG=962382

Change-Id: Ida7e6f57694abe2cbc991446890386b3b4e9ac79
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1613707
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Stefan Zager <szager@chromium.org>
Cr-Commit-Position: refs/heads/master@{#662469}