This moves BindGroupLayoutBase::BindingInfo into the dawn_native
namespace and changes ShaderModule::BindingInfo to extend it with
SPIR-V ids.
Bug: dawn:354
Change-Id: I6a2187e94c0200bee729cf8290f74e4f8c648334
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/17920
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>