Implemented failIfMajorPerformanceCaveat WebGL context creation attribute.

gpu/command_buffer/common/gles2_cmd_utils.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.
 
 // This file is here so other GLES2 related files can have a common set of
 // includes where appropriate.
 
 #ifndef GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_UTILS_H_
 #define GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_UTILS_H_
 
@@ skipping 175 matching lines @@
   int32 blue_size_;
   int32 green_size_;
   int32 red_size_;
   int32 depth_size_;
   int32 stencil_size_;
   int32 samples_;
   int32 sample_buffers_;
   bool buffer_preserved_;
   bool share_resources_;
   bool bind_generates_resource_;
+  bool fail_if_major_perf_caveat_;
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_UTILS_H_