Add an enable D3D11 flag and blacklist specific intel drivers and windows vista from using D3D11.

ui/gl/gl_switches.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gl/gl_switches.h"
 #include "base/basictypes.h"
 
 namespace gfx {
 
 const char kGLImplementationDesktopName[]     = "desktop";
 const char kGLImplementationOSMesaName[]      = "osmesa";
 const char kGLImplementationAppleName[]       = "apple";
 const char kGLImplementationEGLName[]         = "egl";
 const char kGLImplementationSwiftShaderName[] = "swiftshader";
 const char kGLImplementationMockName[]        = "mock";
 
 }  // namespace gfx
 
 namespace switches {
 
+// Enables use of D3D11 when available.
+const char kEnableD3D11[]                   = "enable-d3d11";
+
 // Disables use of D3D11.
 const char kDisableD3D11[]                  = "disable-d3d11";
 
 // Stop the GPU from synchronizing on the vsync before presenting.
 const char kDisableGpuVsync[]               = "disable-gpu-vsync";
 
 // Turns on GPU logging (debug build only).
 const char kEnableGPUServiceLogging[]       = "enable-gpu-service-logging";
 const char kEnableGPUClientLogging[]        = "enable-gpu-client-logging";
 
@@ skipping 32 matching lines @@
 
 // Flag used for Linux tests: for desktop GL bindings, try to load this GL
 // library first, but fall back to regular library if loading fails.
 const char kTestGLLib[]                     = "test-gl-lib";
 
 // This is the list of switches passed from this file that are passed from the
 // GpuProcessHost to the GPU Process. Add your switch to this list if you need
 // to read it in the GPU process, else don't add it.
 const char* kGLSwitchesCopiedFromGpuProcessHost[] = {
   kDisableGpuVsync,
+  kEnableD3D11,
   kDisableD3D11,
   kEnableGPUServiceLogging,
   kEnableGPUServiceTracing,
   kGpuNoContextLost,
   kGpuSwitching,
 };
 const int kGLSwitchesCopiedFromGpuProcessHostNumSwitches =
     arraysize(kGLSwitchesCopiedFromGpuProcessHost);
 
 }  // namespace switches