webnn: support 0D input and empty axes for reduction on CoreML
Neither 0D input nor empty axes are supported by CoreML, and they
can be handled the same way - apply reduction function to the individual
value(s).
Added a test case for empty axes. Reduction WPTs are splitted up to
avoid timeouts.
Bug: 340297707
Change-Id: Ic4d96d29e3c4db1730e18c2e2267a419e109f760
Cq-Include-Trybots: luci.chromium.try:mac14-blink-rel,mac14.arm64-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5742083
Auto-Submit: Phillis Tang phillis@chromium.org
Reviewed-by: Austin Sullivan asully@chromium.org
Reviewed-by: Robert Flack flackr@chromium.org
Commit-Queue: Robert Flack flackr@chromium.org
Cr-Commit-Position: refs/heads/main@{#1335547}