diff -r 000000000000 -r 6474c204b198 widget/windows/winrt/MetroD3DCheckHelper.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/windows/winrt/MetroD3DCheckHelper.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,96 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#pragma once
+
+/* this file is included by exe stubs, don't pull xpcom into it. */
+
+#include <d3d10_1.h>
+#include <dxgi.h>
+#include <d3d10misc.h>
+
+/*
+ * Checks to see if the d3d implementation supports feature level 9.3 or
+ * above. Metrofx can't run on systems that fail this check.
+ *
+ * Note, this can hit perf, don't call this unless you absolutely have to.
+ * Both the ceh and winrt widget code save a cached result in the registry.
+ */
+static bool D3DFeatureLevelCheck()
+{
+  HMODULE dxgiModule = LoadLibraryA("dxgi.dll");
+  if (!dxgiModule) {
+    return false;
+  }
+  decltype(CreateDXGIFactory1)* createDXGIFactory1 =
+    (decltype(CreateDXGIFactory1)*) GetProcAddress(dxgiModule, "CreateDXGIFactory1");
+  if (!createDXGIFactory1) {
+    FreeLibrary(dxgiModule);
+    return false;
+  }
+
+  HMODULE d3d10module = LoadLibraryA("d3d10_1.dll");
+  if (!d3d10module) {
+    FreeLibrary(dxgiModule);
+    return false;
+  }
+  decltype(D3D10CreateDevice1)* createD3DDevice =
+    (decltype(D3D10CreateDevice1)*) GetProcAddress(d3d10module,
+                                                   "D3D10CreateDevice1");
+  if (!createD3DDevice) {
+    FreeLibrary(d3d10module);
+    FreeLibrary(dxgiModule);
+    return false;
+  }
+
+  IDXGIFactory1* factory1;
+  if (FAILED(createDXGIFactory1(__uuidof(IDXGIFactory1), (void**)&factory1))) {
+    FreeLibrary(d3d10module);
+    FreeLibrary(dxgiModule);
+    return false;
+  }
+
+  IDXGIAdapter1* adapter1;
+  if (FAILED(factory1->EnumAdapters1(0, &adapter1))) {
+    factory1->Release();
+    FreeLibrary(d3d10module);
+    FreeLibrary(dxgiModule);
+    return false;
+  }
+
+  // Try for DX10.1
+  ID3D10Device1* device;
+  if (FAILED(createD3DDevice(adapter1, D3D10_DRIVER_TYPE_HARDWARE, nullptr,
+                             D3D10_CREATE_DEVICE_BGRA_SUPPORT |
+                             D3D10_CREATE_DEVICE_PREVENT_INTERNAL_THREADING_OPTIMIZATIONS,
+                             D3D10_FEATURE_LEVEL_10_1,
+                             D3D10_1_SDK_VERSION, &device))) {
+    // Try for DX10
+    if (FAILED(createD3DDevice(adapter1, D3D10_DRIVER_TYPE_HARDWARE, nullptr,
+                               D3D10_CREATE_DEVICE_BGRA_SUPPORT |
+                               D3D10_CREATE_DEVICE_PREVENT_INTERNAL_THREADING_OPTIMIZATIONS,
+                               D3D10_FEATURE_LEVEL_10_0,
+                               D3D10_1_SDK_VERSION, &device))) {
+      // Try for DX9.3 (we fall back to cairo and cairo has support for D3D 9.3)
+      if (FAILED(createD3DDevice(adapter1, D3D10_DRIVER_TYPE_HARDWARE, nullptr,
+                                 D3D10_CREATE_DEVICE_BGRA_SUPPORT |
+                                 D3D10_CREATE_DEVICE_PREVENT_INTERNAL_THREADING_OPTIMIZATIONS,
+                                 D3D10_FEATURE_LEVEL_9_3,
+                                 D3D10_1_SDK_VERSION, &device))) {
+        adapter1->Release();
+        factory1->Release();
+        FreeLibrary(d3d10module);
+        FreeLibrary(dxgiModule);
+        return false;
+      }
+    }
+  }
+  device->Release();
+  adapter1->Release();
+  factory1->Release();
+  FreeLibrary(d3d10module);
+  FreeLibrary(dxgiModule);
+  return true;
+}