adds WARP support to Chromium, for Metro mode only, on Windows 8

gpu/config/gpu_info.h

Index: gpu/config/gpu_info.h
diff --git a/gpu/config/gpu_info.h b/gpu/config/gpu_info.h
index d092c3a335c320af4b3430cb97d345fd5e75fb3a..c8cb93101aaa1ccd3ac172c719d258255978cba0 100644
--- a/gpu/config/gpu_info.h
+++ b/gpu/config/gpu_info.h
@@ -137,6 +137,9 @@ struct GPU_EXPORT GPUInfo {
   // reset detection or notification not available.
   uint32 gl_reset_notification_strategy;
 
+  // True if the GPU process should use WARP on Windows.
+  bool use_warp;
+
   // The device semantics, i.e. whether the Vista and Windows 7 specific
   // semantics are available.
   bool can_lose_context;