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

content/public/browser/gpu_data_manager.h

Index: content/public/browser/gpu_data_manager.h
diff --git a/content/public/browser/gpu_data_manager.h b/content/public/browser/gpu_data_manager.h
index 7ffc9f18402a86cc082738bac939854dc394476f..ee2637bd748af6b2b2b3993c0331dde188b661bb 100644
--- a/content/public/browser/gpu_data_manager.h
+++ b/content/public/browser/gpu_data_manager.h
@@ -94,6 +94,14 @@ class GpuDataManager {
                             std::string* gl_renderer,
                             std::string* gl_version) = 0;
 
+  // Tells the data manager that it should use WARP software rendering on
+  // Windows. This state will persist between program runs.
+  virtual void SetShouldUseWarp(bool use_warp) = 0;
+
+  // Returns current state about WARP, which may be due to command-line
+  // arguments or saved state.
+  virtual bool ShouldUseWarp() const = 0;
+
   // Turn off all hardware acceleration.
   virtual void DisableHardwareAcceleration() = 0;