webnn: Support the gatherElements operator in CoreML
Negative and OOB indices are not yet supported
Bug: 41481333
Cq-Include-Trybots: luci.chromium.try:mac15-blink-rel,mac15.arm64-blink-rel,mac14-blink-rel,mac14.arm64-blink-rel,win11-blink-rel
Change-Id: Idb5e193347c5989927daa5cf60c3b58430fbb88c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5941495
Reviewed-by: Phillis Tang phillis@chromium.org
Auto-Submit: Austin Sullivan asully@chromium.org
Commit-Queue: Phillis Tang phillis@chromium.org
Cr-Commit-Position: refs/heads/main@{#1372166}