[iOS] Enable the shortcuts widget flag

Change-Id: I925879fa76df34d360c64b47e28ebbaa5a21475a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4556425


Commit-Queue: Aliaa Alborhamy <aliaaborhamy@google.com>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1148426}