WebNN: Change argMin/argMax to take scalar axis
This CL changes argMin/argMax to take scalar axis to align with the spec
change [1].
The changes include the definition of IDL and mojo, the implementation
of DirectML, TfLite and CoreML backend and the related unit tests and
WPT tests.
[1] webmachinelearning/webnn#724
Bug: 352359898
Change-Id: Iee68b568331570a6ea51fd17b2195c602d4cff59
Cq-Include-Trybots: luci.chromium.try:win11-blink-rel,mac14.arm64-blink-rel,mac14-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5721028
Reviewed-by: Alex Gough ajgo@chromium.org
Reviewed-by: Phillis Tang phillis@chromium.org
Commit-Queue: Bin Miao bin.miao@intel.com
Reviewed-by: ningxin hu ningxin.hu@intel.com
Cr-Commit-Position: refs/heads/main@{#1331567}