Add support for all blendmodes if we have GL_KHR_blend_equation_advanced.

gpu/command_buffer/client/gles2_implementation_impl_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 2144 matching lines @@
 }
 
 void GLES2Implementation::MatrixLoadIdentityCHROMIUM(GLenum matrixMode) {
   GPU_CLIENT_SINGLE_THREAD_CHECK();
   GPU_CLIENT_LOG("[" << GetLogPrefix() << "] glMatrixLoadIdentityCHROMIUM("
                      << GLES2Util::GetStringMatrixMode(matrixMode) << ")");
   helper_->MatrixLoadIdentityCHROMIUM(matrixMode);
   CheckGLError();
 }
 
+void GLES2Implementation::BlendBarrierKHR() {
+  GPU_CLIENT_SINGLE_THREAD_CHECK();
+  GPU_CLIENT_LOG("[" << GetLogPrefix() << "] glBlendBarrierKHR("
+                     << ")");
+  helper_->BlendBarrierKHR();
+  CheckGLError();
+}
+
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_IMPL_AUTOGEN_H_