Capture/Replay: Don't finish() destroyed Contexts If an app destroys a context, but keeps it current on a thread, ANGLE will reset the context, but can't delete it. This can lead to a segfault if ANGLE attempts to call Context::finish() on a destroyed context. To solve this, check if the context has been destroyed in ShareGroup::finishAllContexts(). Bug: angleproject:6653 Change-Id: Ib30e352ad6395e01f8fab0095cd6231dfb10d8ae Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3260726 Reviewed-by: Cody Northrop <cnorthrop@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Tim Van Patten <timvp@google.com>