[wv] Propagate onRenderProcessGone exceptions back to the application.

If an exception is thrown in onRenderProcessGone, then it should be
propagated back to the UI thread message loop so that it is observable
by the application/debuggerd as something other than a native crash.

Bug: 592556
Change-Id: I28b6792c4503347092ce4e79370b20de87c51114
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1585881
Commit-Queue: Tobias Sargeant <tobiasjs@chromium.org>
Reviewed-by: Richard Coles <torne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663026}
5 files changed