This removes the thread-local field in question. This side-channel for
the "caught exception" is not needed, we can just explicitly pass the
exception value to all support functions. Also, there is an inherent
problem with having this side-channel, as it will not be properly reset
when an exception handler ends up not rethrowing the exception.

R=ahaas@chromium.org
BUG=v8:8097

Change-Id: I2fdaff89f0eb318ce5a33bf56513165185547c1b
Reviewed-on: https://chromium-review.googlesource.com/1194063Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55517}