Drive-by fix: In ProcessFeedbackForGlobalAccess, we had forgotten to
return the feedback when it already existed.

Bug: v8:7790, v8:9094
Change-Id: Ie4be6cef5755bbdd9d8ed472caaa2e32d243893d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1554680Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60705}