Mark SwapBuffers for an offscreen surface as unimplemented

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"
 
 namespace gpu {
 namespace gles2 {
@@ skipping 2445 matching lines @@
       glIsVertexArrayOES(GetVertexArrayServiceID(array, &vertex_array_id_map_));
   return error::kNoError;
 }
 
 error::Error GLES2DecoderPassthroughImpl::DoBindVertexArrayOES(GLuint array) {
   glBindVertexArrayOES(GetVertexArrayServiceID(array, &vertex_array_id_map_));
   return error::kNoError;
 }
 
 error::Error GLES2DecoderPassthroughImpl::DoSwapBuffers() {
+  if (offscreen_) {
+    NOTIMPLEMENTED();
+    return error::kNoError;
+  }
+
   gfx::SwapResult result = surface_->SwapBuffers();
   if (result == gfx::SwapResult::SWAP_FAILED) {
     LOG(ERROR) << "Context lost because SwapBuffers failed.";
   }
   // TODO(geofflang): force the context loss?
   return error::kNoError;
 }
 
 error::Error GLES2DecoderPassthroughImpl::DoGetMaxValueInBufferCHROMIUM(
     GLuint buffer_id,
@@ skipping 846 matching lines @@
     GLuint texture,
     GLboolean promotion_hint,
     GLint display_x,
     GLint display_y) {
   NOTIMPLEMENTED();
   return error::kNoError;
 }
 
 }  // namespace gles2
 }  // namespace gpu