Improve D3D12 adapter initialization.

Gather device info at device initialization rather than adapter initialization.

BUG=dawn:144

Change-Id: I07e114731a37f3738daa585afa99675f2fd36289
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/7700
Commit-Queue: Bryan Bernhart <bryan.bernhart@intel.com>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index 1e04c69..c859ff8 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -176,6 +176,8 @@
       "src/dawn_native/d3d12/CommandBufferD3D12.h",
       "src/dawn_native/d3d12/ComputePipelineD3D12.cpp",
       "src/dawn_native/d3d12/ComputePipelineD3D12.h",
+      "src/dawn_native/d3d12/D3D12Info.cpp",
+      "src/dawn_native/d3d12/D3D12Info.h",
       "src/dawn_native/d3d12/DescriptorHeapAllocator.cpp",
       "src/dawn_native/d3d12/DescriptorHeapAllocator.h",
       "src/dawn_native/d3d12/DeviceD3D12.cpp",