Make Callback::Reset() return a copy to support use-cases where Run() ends up modifying |*this|.

media/base/composite_filter.cc

 // Copyright (c) 2012 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 "media/base/composite_filter.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
+#include "base/callback_helpers.h"
 #include "base/message_loop.h"
 #include "base/stl_util.h"
 
 namespace media {
 
 class CompositeFilter::FilterHostImpl : public FilterHost {
  public:
   FilterHostImpl(CompositeFilter* parent, FilterHost* host);
 
   FilterHost* host();
@@ skipping 264 matching lines @@
     default:
       ChangeState(kError);
       DispatchPendingCallback(PIPELINE_ERROR_INVALID_STATE);
   }
 }
 
 void CompositeFilter::DispatchPendingCallback(PipelineStatus status) {
   DCHECK(status_cb_.is_null() ^ callback_.is_null());
 
   if (!status_cb_.is_null()) {
-    ResetAndRunCB(&status_cb_, status);
+    base::ResetAndReturn(&status_cb_).Run(status);
     return;
   }
 
   if (!callback_.is_null()) {
     if (status != PIPELINE_OK)
       SendErrorToHost(status);
-    ResetAndRunCB(&callback_);
+    base::ResetAndReturn(&callback_).Run();
   }
 }
 
 CompositeFilter::State CompositeFilter::GetNextState(State state) const {
   State ret = kInvalid;
   switch (state) {
     case kPlayPending:
       ret = kPlaying;
       break;
     case kPausePending:
@@ skipping 181 matching lines @@
 
 void CompositeFilter::FilterHostImpl::NotifyEnded() {
   host_->NotifyEnded();
 }
 
 void CompositeFilter::FilterHostImpl::DisableAudioRenderer() {
   host_->DisableAudioRenderer();
 }
 
 }  // namespace media