Initialize remaining passthrough command decoder caps.

gpu/command_buffer/service/gles2_cmd_decoder_passthrough_doers.cc

 // Copyright (c) 2016 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.
 
 #include "gpu/command_buffer/service/gles2_cmd_decoder_passthrough.h"
 
 #include "base/strings/string_number_conversions.h"
 #include "ui/gl/gl_version_info.h"
 
 namespace gpu {
@@ skipping 3304 matching lines @@
   }
   // TODO(geofflang): force the context loss?
   return error::kNoError;
 }
 
 error::Error GLES2DecoderPassthroughImpl::DoPostSubBufferCHROMIUM(
     GLint x,
     GLint y,
     GLint width,
     GLint height) {
+  if (!surface_->SupportsPostSubBuffer()) {
+    InsertError(GL_INVALID_OPERATION,
+                "glPostSubBufferCHROMIUM is not supported for this surface.");
+    return error::kNoError;
+  }
+
+  gfx::SwapResult result = surface_->PostSubBuffer(x, y, width, height);
+  if (result == gfx::SwapResult::SWAP_FAILED) {
+    LOG(ERROR) << "Context lost because PostSubBuffer failed.";
+  }
+  // TODO(geofflang): force the context loss?
   return error::kNoError;
 }
 
 error::Error GLES2DecoderPassthroughImpl::DoCopyTextureCHROMIUM(
     GLuint source_id,
     GLint source_level,
     GLenum dest_target,
     GLuint dest_id,
     GLint dest_level,
     GLint internalformat,
@@ skipping 703 matching lines @@
 }
 
 error::Error GLES2DecoderPassthroughImpl::DoSetEnableDCLayersCHROMIUM(
     GLboolean enable) {
   NOTIMPLEMENTED();
   return error::kNoError;
 }
 
 }  // namespace gles2
 }  // namespace gpu