[ios] Fixes VoiceOver for the lockscreen launcher widgets.

Fixed: 1359394
Change-Id: Ibfada5dd00b29e80c7114025875a84f95cdf064b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3872166


Reviewed-by: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Robbie Gibson <rkgibson@google.com>
Commit-Queue: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1042727}