Rename mock_webgpu to mock_api and define the function "GetProcTableAndDevice" to "GetProcTable" for removing the special arguments "WGPUDevice* device" that can be got with "GetNewDevice()".
BUG=dawn:1201
Change-Id: I4fc47e4497ba4b6d280cc8af8605f1d93f43497e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/72761
Reviewed-by: Jiawei Shao <jiawei.shao@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Junwei Fu <junwei.fu@intel.com>