webnn: utilize constant nodes in DirectML backend
This CL utilizes DML_GRAPH_NODE_TYPE_CONSTANT introduced in
DML_FEATURE_LEVEL_6_2 for constant scalar inputs, which allows CPU
memory to be directly consumed during graph compilation.
Change-Id: I468e600e0b1dae59a0ab017ef7fe86b5e0e00c59
Bug: 366284850
Cq-Include-Trybots: luci.chromium.try:win11-blink-rel, mac14.arm64-blink-rel, mac14-blink-rel, mac15.arm64-blink-rel, mac15-blink-rel, linux-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5859935
Reviewed-by: Rafael Cintron rafael.cintron@microsoft.com
Commit-Queue: Shiyi Zou shiyi.zou@intel.com
Reviewed-by: ningxin hu ningxin.hu@intel.com
Auto-Submit: Shiyi Zou shiyi.zou@intel.com
Cr-Commit-Position: refs/heads/main@{#1367255}