This CL implements RequestDevice and also has changes for
Dawn to internally use wgpu::FeatureName enums, instead of
strings. Some of the string handling is kept for now to
support the deprecated creation path. GetFeatureInfo is added
to the instance to get a name and description of the feature,
for reporting in about://gpu.
Dawn device toggles are now passed in an extension struct off
of the device descriptor. This is only supported in dawn_native,
and not dawn_wire, for now, since dawn_wire doesn't have a way
to serialize lists of null-terminated const char*.
To enable the client to check whether the toggle descriptor is
supported, a `dawn-native` feature is added which is supported
all the time with dawn_native, but not supported with dawn_wire.
Feature `dawn-native` also enables a synchronous version of
CreateDevice for convenience.
Bug: dawn:160
Change-Id: Ifc195e7ea808c6c319021528ef4b36bd65583bff
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/72020
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
2f218e2b21