We landed two mitigations for the bug, and crash data shows that it is
indeed fixed. It is still not clear whether this is a compiler bug,
wrong use of inline assembly, or LTO. The original fix to move the call
to {FlushInstructionCache} should not be needed any more though.
This CL thus reverts https://crrev.com/c/1571619 and uses V8_NOINLINE
instead of the noinline attribute.
If this reintroduces any crashes, please revert. We are far enough away
from the branch to detect this on canary without too much trouble.

R=jkummerow@chromium.org

Bug: chromium:952759
Change-Id: I76f9850d8d6a8af0926b88e961f89df41b662ae7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1611677Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61477}