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

gpu/config/gpu_info.h

 // 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.
 
 #ifndef GPU_CONFIG_GPU_INFO_H_
 #define GPU_CONFIG_GPU_INFO_H_
 
 // Provides access to the GPU information for the system
 // on which chrome is currently running.
 
@@ skipping 119 matching lines @@
   // GL window system binding version.  "" if not available.
   std::string gl_ws_version;
 
   // GL window system binding extensions.  "" if not available.
   std::string gl_ws_extensions;
 
   // GL reset notification strategy as defined by GL_ARB_robustness. 0 if GPU
   // 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;
 
   // By default all values are 0.
   GpuPerformanceStats performance_stats;
 
   bool software_rendering;
 
   // Whether the driver uses direct rendering. True on most platforms, false on
@@ skipping 43 matching lines @@
     virtual ~Enumerator() {}
   };
 
   // Outputs the fields in this structure to the provided enumerator.
   void EnumerateFields(Enumerator* enumerator) const;
 };
 
 }  // namespace gpu
 
 #endif  // GPU_CONFIG_GPU_INFO_H_