Changes dawn::native procs to correctly convert C++ enum and bitmask
returns values.
Bug: dawn:1451
Change-Id: I39a8d218f76e25b178a83eeb99d653222d39d040
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/92440
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>