[ios] Migrates resources to use bundle_data_xcassets.

# Skipping the trademarked image presubmit for an existing
# (non-trademarked) image file.
NOPRESUBMIT=true

Bug: 332929378
Change-Id: I85a7dd893b14754a4546315589b8ddef9032675f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5426379


Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1283127}