Math fast-path cannot drop arguments because their side-effects
must be preserved. For example, Math.imul(x) dropped x entirely,
because if x is convertible to an integer, the result is 0.
This, however, is not OK because converting x to an integer might
throw.

Bug: chromium:818070, v8:7250, v8:7240
Change-Id: I8363e6dcd3fc78c879395aacb636d5782c3b023e
Reviewed-on: https://chromium-review.googlesource.com/948523Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51736}