The scenario here: the asm function fails asm validation,
so we emit a message. In doing so, we create a JSValue wrapper for
the script object that we cache on the script object. This wrapper
is context-dependent and causes the code serializer to choke.

R=mtrofin@chromium.org, titzer@chromium.org
BUG=chromium:674446,chromium:673321

Review-Url: https://codereview.chromium.org/2586943003
Cr-Commit-Position: refs/heads/master@{#41794}