In the WebAssembly.Global constructor we continued to execute even after
the JavaScript code in the descriptor.mutable getter threw an exception.
This caused a problem when the descriptor.value getter was executed even
though there was a scheduled exception.

R=jkummerow@chromium.org

Bug: chromium:1033948
Change-Id: Idac554175fe45ec677447b793db069eb6de543b7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1993283Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65669}