Perform glReadPixels with PBOs in the gpu, if PBOs are available.

gpu/command_buffer/common/gles2_cmd_format_autogen.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 auto-generated from
 // gpu/command_buffer/build_gles2_cmd_buffer.py
 // DO NOT EDIT!
 
 #ifndef GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_FORMAT_AUTOGEN_H_
 #define GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_FORMAT_AUTOGEN_H_
@@ skipping 4869 matching lines @@
     return static_cast<uint32>(sizeof(ValueType));  // NOLINT
   }
 
   void SetHeader() {
     header.SetCmd<ValueType>();
   }
 
   void Init(
       GLint _x, GLint _y, GLsizei _width, GLsizei _height, GLenum _format,
       GLenum _type, uint32 _pixels_shm_id, uint32 _pixels_shm_offset,
-      uint32 _result_shm_id, uint32 _result_shm_offset) {
+      uint32 _result_shm_id, uint32 _result_shm_offset, GLboolean _async) {
     SetHeader();
     x = _x;
     y = _y;
     width = _width;
     height = _height;
     format = _format;
     type = _type;
     pixels_shm_id = _pixels_shm_id;
     pixels_shm_offset = _pixels_shm_offset;
     result_shm_id = _result_shm_id;
     result_shm_offset = _result_shm_offset;
+    async = _async;
   }
 
   void* Set(
       void* cmd, GLint _x, GLint _y, GLsizei _width, GLsizei _height,
       GLenum _format, GLenum _type, uint32 _pixels_shm_id,
       uint32 _pixels_shm_offset, uint32 _result_shm_id,
-      uint32 _result_shm_offset) {
+      uint32 _result_shm_offset, GLboolean _async) {
     static_cast<ValueType*>(
         cmd)->Init(
             _x, _y, _width, _height, _format, _type, _pixels_shm_id,
-            _pixels_shm_offset, _result_shm_id, _result_shm_offset);
+            _pixels_shm_offset, _result_shm_id, _result_shm_offset, _async);
     return NextCmdAddress<ValueType>(cmd);
   }
 
   gpu::CommandHeader header;
   int32 x;
   int32 y;
   int32 width;
   int32 height;
   uint32 format;
   uint32 type;
   uint32 pixels_shm_id;
   uint32 pixels_shm_offset;
   uint32 result_shm_id;
   uint32 result_shm_offset;
+  uint32 async;
 };
 
-COMPILE_ASSERT(sizeof(ReadPixels) == 44,
-               Sizeof_ReadPixels_is_not_44);
+COMPILE_ASSERT(sizeof(ReadPixels) == 48,
+               Sizeof_ReadPixels_is_not_48);
 COMPILE_ASSERT(offsetof(ReadPixels, header) == 0,
                OffsetOf_ReadPixels_header_not_0);
 COMPILE_ASSERT(offsetof(ReadPixels, x) == 4,
                OffsetOf_ReadPixels_x_not_4);
 COMPILE_ASSERT(offsetof(ReadPixels, y) == 8,
                OffsetOf_ReadPixels_y_not_8);
 COMPILE_ASSERT(offsetof(ReadPixels, width) == 12,
                OffsetOf_ReadPixels_width_not_12);
 COMPILE_ASSERT(offsetof(ReadPixels, height) == 16,
                OffsetOf_ReadPixels_height_not_16);
 COMPILE_ASSERT(offsetof(ReadPixels, format) == 20,
                OffsetOf_ReadPixels_format_not_20);
 COMPILE_ASSERT(offsetof(ReadPixels, type) == 24,
                OffsetOf_ReadPixels_type_not_24);
 COMPILE_ASSERT(offsetof(ReadPixels, pixels_shm_id) == 28,
                OffsetOf_ReadPixels_pixels_shm_id_not_28);
 COMPILE_ASSERT(offsetof(ReadPixels, pixels_shm_offset) == 32,
                OffsetOf_ReadPixels_pixels_shm_offset_not_32);
 COMPILE_ASSERT(offsetof(ReadPixels, result_shm_id) == 36,
                OffsetOf_ReadPixels_result_shm_id_not_36);
 COMPILE_ASSERT(offsetof(ReadPixels, result_shm_offset) == 40,
                OffsetOf_ReadPixels_result_shm_offset_not_40);
+COMPILE_ASSERT(offsetof(ReadPixels, async) == 44,
+               OffsetOf_ReadPixels_async_not_44);
 
 struct ReleaseShaderCompiler {
   typedef ReleaseShaderCompiler ValueType;
   static const CommandId kCmdId = kReleaseShaderCompiler;
   static const cmd::ArgFlags kArgFlags = cmd::kFixed;
 
   static uint32 ComputeSize() {
     return static_cast<uint32>(sizeof(ValueType));  // NOLINT
   }
 
@@ skipping 6066 matching lines @@
 COMPILE_ASSERT(sizeof(DrawBuffersEXTImmediate) == 8,
                Sizeof_DrawBuffersEXTImmediate_is_not_8);
 COMPILE_ASSERT(offsetof(DrawBuffersEXTImmediate, header) == 0,
                OffsetOf_DrawBuffersEXTImmediate_header_not_0);
 COMPILE_ASSERT(offsetof(DrawBuffersEXTImmediate, count) == 4,
                OffsetOf_DrawBuffersEXTImmediate_count_not_4);
 
 
 #endif  // GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_FORMAT_AUTOGEN_H_