i32 stack parameters can be loaded by Turbofan as 64-bit value, hence
they would not be zero extended. If this loaded value is then passed to
Liftoff (which assumes zero-extended i32 values), we could use it for
memory accesses, which would be out of bounds.

R=mstarzinger@chromium.org

Bug: chromium:864509, v8:6600
Change-Id: I0f45a269b1fb1c2befc2e6bc660c559a88323767
Reviewed-on: https://chromium-review.googlesource.com/1140168
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54500}