Remove ContextProvider::IsContextLost.

ui/compositor/test/in_process_context_provider.cc

 // Copyright (c) 2013 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 "ui/compositor/test/in_process_context_provider.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/lazy_instance.h"
 #include "base/strings/stringprintf.h"
@@ skipping 171 matching lines @@
     gr_context_.get()->resetContext(state);
 }
 
 void InProcessContextProvider::SetupLock() {
 }
 
 base::Lock* InProcessContextProvider::GetLock() {
   return &context_lock_;
 }
 
-bool InProcessContextProvider::IsContextLost() {
-  DCHECK(context_thread_checker_.CalledOnValidThread());
-
-  base::AutoLock lock(destroyed_lock_);
-  return destroyed_;
-}
-
 void InProcessContextProvider::VerifyContexts() {
 }
 
 void InProcessContextProvider::DeleteCachedResources() {
   DCHECK(context_thread_checker_.CalledOnValidThread());
 
   if (gr_context_) {
     TRACE_EVENT_INSTANT0("gpu", "GrContext::freeGpuResources",
                          TRACE_EVENT_SCOPE_THREAD);
     gr_context_->freeGpuResources();
@@ skipping 25 matching lines @@
       return;
     destroyed_ = true;
   }
   if (!lost_context_callback_.is_null())
     base::ResetAndReturn(&lost_context_callback_).Run();
   if (gr_context_)
     gr_context_->abandonContext();
 }
 
 }  // namespace ui