Remove a DCHECK in BitmapUploader which causes crash in some unittests

components/bitmap_uploader/bitmap_uploader.cc

 // Copyright 2015 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 "components/bitmap_uploader/bitmap_uploader.h"
 
 #include <stddef.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 31 matching lines @@
 void BitmapUploader::Init(shell::Connector* connector) {
   surface_ = window_->RequestSurface(mus::mojom::SurfaceType::DEFAULT);
   surface_->BindToThread();
   surface_->set_client(this);
 
   connector->ConnectToInterface("mojo:mus", &gpu_service_);
   mus::mojom::CommandBufferPtr gles2_client;
   gpu_service_->CreateOffscreenGLES2Context(GetProxy(&gles2_client));
   gles2_context_.reset(new mus::GLES2Context(
       std::vector<int32_t>(), gles2_client.PassInterface().PassHandle()));
-  DCHECK(gles2_context_->Initialize());
+  if (!gles2_context_->Initialize())
+    gles2_context_.reset();

[sadrul, 2016/05/26 15:41:35]

Can you add a DCHECK here that if Initialize() returns false, then that's
because gpu_service_ had an error of some sort, i.e. install a
set_connection_error_handler on |gpu_service_|, and DCHECK that the handler was
called if Initialize() returned false?

[Peng, 2016/05/30 14:04:25]

gpu_service_.encountered_error() is not true at here.
But if command_buffer_.encountered_error() is true at
https://code.google.com/p/chromium/codesearch#chromium/src/components/mus/pub...
.

Any thought?

 }
 
 // Sets the color which is RGBA.
 void BitmapUploader::SetColor(uint32_t color) {
   if (color_ == color)
     return;
   color_ = color;
   if (surface_)
     Upload();
 }
@@ skipping 164 matching lines @@
     DCHECK_EQ(1, resource->count);
     gl->WaitSyncTokenCHROMIUM(resource->sync_token.GetConstData());
     uint32_t texture_id = resource_to_texture_id_map_[resource->id];
     DCHECK_NE(0u, texture_id);
     resource_to_texture_id_map_.erase(resource->id);
     gl->DeleteTextures(1, &texture_id);
   }
 }
 
 }  // namespace bitmap_uploader