DCHECK if shader compilation fails that it's due to context loss.

mojo/gles2/command_buffer_client_impl.cc

 // 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.
 
 #include "mojo/gles2/command_buffer_client_impl.h"
 
 #include <limits>
 
 #include "base/logging.h"
 #include "base/process/process_handle.h"
@@ skipping 317 matching lines @@
     return;
   }
 
   if (state->generation - last_state_.generation < 0x80000000U)
     last_state_ = state.To<State>();
 }
 
 void CommandBufferClientImpl::SetLock(base::Lock* lock) {
 }
 
+bool CommandBufferClientImpl::IsGpuChannelLost() {
+  // This is only possible for out-of-process command buffers.
+  return false;
+}
+
 }  // namespace gles2