Add support for all blendmodes if we have GL_KHR_blend_equation_advanced.

gpu/command_buffer/common/gles2_cmd_format_autogen.h

 // Copyright 2014 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
 // It's formatted by clang-format using chromium coding style:
 //    clang-format -i -style=chromium filename
 // DO NOT EDIT!
 
@@ skipping 8996 matching lines @@
   uint32_t matrixMode;
 };
 
 COMPILE_ASSERT(sizeof(MatrixLoadIdentityCHROMIUM) == 8,
                Sizeof_MatrixLoadIdentityCHROMIUM_is_not_8);
 COMPILE_ASSERT(offsetof(MatrixLoadIdentityCHROMIUM, header) == 0,
                OffsetOf_MatrixLoadIdentityCHROMIUM_header_not_0);
 COMPILE_ASSERT(offsetof(MatrixLoadIdentityCHROMIUM, matrixMode) == 4,
                OffsetOf_MatrixLoadIdentityCHROMIUM_matrixMode_not_4);
 
+struct BlendBarrierKHR {
+  typedef BlendBarrierKHR ValueType;
+  static const CommandId kCmdId = kBlendBarrierKHR;
+  static const cmd::ArgFlags kArgFlags = cmd::kFixed;
+  static const uint8 cmd_flags = CMD_FLAG_SET_TRACE_LEVEL(3);
+
+  static uint32_t ComputeSize() {
+    return static_cast<uint32_t>(sizeof(ValueType));  // NOLINT
+  }
+
+  void SetHeader() { header.SetCmd<ValueType>(); }
+
+  void Init() { SetHeader(); }
+
+  void* Set(void* cmd) {
+    static_cast<ValueType*>(cmd)->Init();
+    return NextCmdAddress<ValueType>(cmd);
+  }
+
+  gpu::CommandHeader header;
+};
+
+COMPILE_ASSERT(sizeof(BlendBarrierKHR) == 4, Sizeof_BlendBarrierKHR_is_not_4);
+COMPILE_ASSERT(offsetof(BlendBarrierKHR, header) == 0,
+               OffsetOf_BlendBarrierKHR_header_not_0);
+
 #endif  // GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_FORMAT_AUTOGEN_H_