Implement native GMB backbuffers in the GLES2 Command Decoder.

gpu/command_buffer/common/gles2_cmd_utils.cc

 // 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.
 
 #include <sstream>
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>
@@ skipping 1765 matching lines @@
 const int32_t kSamples = 0x3031;          // EGL_SAMPLES
 const int32_t kSampleBuffers = 0x3032;    // EGL_SAMPLE_BUFFERS
 const int32_t kNone = 0x3038;             // EGL_NONE
 const int32_t kSwapBehavior = 0x3093;     // EGL_SWAP_BEHAVIOR
 const int32_t kBufferPreserved = 0x3094;  // EGL_BUFFER_PRESERVED
 
 // Chromium only.
 const int32_t kBindGeneratesResource = 0x10000;
 const int32_t kFailIfMajorPerfCaveat = 0x10001;
 const int32_t kLoseContextWhenOutOfMemory = 0x10002;
-const int32_t kContextType = 0x10003;
+const int32_t kShouldUseNativeGMBForBackbuffer = 0x10003;
+const int32_t kContextType = 0x10004;
 
 }  // namespace
 
 ContextCreationAttribHelper::ContextCreationAttribHelper()
     : alpha_size(-1),
       blue_size(-1),
       green_size(-1),
       red_size(-1),
       depth_size(-1),
       stencil_size(-1),
       samples(-1),
       sample_buffers(-1),
       buffer_preserved(true),
       bind_generates_resource(true),
       fail_if_major_perf_caveat(false),
       lose_context_when_out_of_memory(false),
+      should_use_native_gmb_for_backbuffer(false),
       context_type(CONTEXT_TYPE_OPENGLES2) {}
 
 ContextCreationAttribHelper::ContextCreationAttribHelper(
     const ContextCreationAttribHelper& other) = default;
 
 bool ContextCreationAttribHelper::Parse(const std::vector<int32_t>& attribs) {
   for (size_t i = 0; i < attribs.size(); i += 2) {
     const int32_t attrib = attribs[i];
     if (i + 1 >= attribs.size()) {
       if (attrib == kNone) {
@@ skipping 36 matching lines @@
         break;
       case kBindGeneratesResource:
         bind_generates_resource = value != 0;
         break;
       case kFailIfMajorPerfCaveat:
         fail_if_major_perf_caveat = value != 0;
         break;
       case kLoseContextWhenOutOfMemory:
         lose_context_when_out_of_memory = value != 0;
         break;
+      case kShouldUseNativeGMBForBackbuffer:
+        should_use_native_gmb_for_backbuffer = value != 0;
+        break;
       case kContextType:
         context_type = static_cast<ContextType>(value);
         break;
       case kNone:
         // Terminate list, even if more attributes.
         return true;
       default:
         DLOG(ERROR) << "Invalid context creation attribute: " << attrib;
         return false;
     }
   }
 
   return true;
 }
 
 #include "gpu/command_buffer/common/gles2_cmd_utils_implementation_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu