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

ui/gl/gl_switches.cc

Index: ui/gl/gl_switches.cc
diff --git a/ui/gl/gl_switches.cc b/ui/gl/gl_switches.cc
index 2649abac806107e78ec258a072e3d0f7352a2c41..6addfe126fc8d21ffd249ab609fb9ab6cb6a2bc4 100644
--- a/ui/gl/gl_switches.cc
+++ b/ui/gl/gl_switches.cc
@@ -18,6 +18,9 @@ const char kGLImplementationMockName[]        = "mock";
 
 namespace switches {
 
+// Enables use of D3D11 when available.
+const char kEnableD3D11[]                   = "enable-d3d11";
+
 // Disables use of D3D11.
 const char kDisableD3D11[]                  = "disable-d3d11";
 
@@ -70,6 +73,7 @@ const char kTestGLLib[]                     = "test-gl-lib";
 // to read it in the GPU process, else don't add it.
 const char* kGLSwitchesCopiedFromGpuProcessHost[] = {
   kDisableGpuVsync,
+  kEnableD3D11,
   kDisableD3D11,
   kEnableGPUServiceLogging,
   kEnableGPUServiceTracing,