Allow textures to be moved from one GL context group to another.

gpu/command_buffer/service/gl_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 includes all the necessary GL headers and implements some useful
 // utilities.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_GL_UTILS_H_
 #define GPU_COMMAND_BUFFER_SERVICE_GL_UTILS_H_
 
@@ skipping 67 matching lines @@
 // GL_EXT_occlusion_query_boolean
 #define GL_ANY_SAMPLES_PASSED_EXT              0x8C2F
 #define GL_ANY_SAMPLES_PASSED_CONSERVATIVE_EXT 0x8D6A
 #define GL_CURRENT_QUERY_EXT                   0x8865
 #define GL_QUERY_RESULT_EXT                    0x8866
 #define GL_QUERY_RESULT_AVAILABLE_EXT          0x8867
 
 // GL_CHROMIUM_command_buffer_query
 #define GL_COMMANDS_ISSUED_CHROMIUM            0x84F2
 
+// GL_CHROMIUM_texture_mailbox
+#define GL_MAILBOX_SIZE_CHROMIUM               32
 
 #define GL_GLEXT_PROTOTYPES 1
 
 // Define this for extra GL error debugging (slower).
 // #define GL_ERROR_DEBUGGING
 #ifdef GL_ERROR_DEBUGGING
 #define CHECK_GL_ERROR() do {                                           \
     GLenum gl_error = glGetError();                                     \
     LOG_IF(ERROR, gl_error != GL_NO_ERROR) << "GL Error :" << gl_error; \
   } while (0)
 #else  // GL_ERROR_DEBUGGING
 #define CHECK_GL_ERROR() void(0)
 #endif  // GL_ERROR_DEBUGGING
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GL_UTILS_H_