Don't crash in TestRecipeReplayer::AllAssertionsPassed

We had a hard crash:
Check failed: is_ok(). Can't ExtractBool() because the script
encountered a problem: a JavaScript error: "RenderFrame deleted."
if TestRecipeReplayer::AllAssertionsPassed().

Instead of CHECK()ing, the the AllAssertionsPassed() function now fails
gracefully. It is called in WaitForElementToBeReady(), so hopefully the
code becomes more robust against ongoing navigations by retrying steps
instead of crashing.

Bug: 446080325
Change-Id: I673def4834a78a5b7c72a1f11bc1fa96554dfa9c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7002866
Commit-Queue: Dominic Battre <battre@chromium.org>
Reviewed-by: Christoph Schwering <schwering@google.com>
Cr-Commit-Position: refs/heads/main@{#1524192}