Improvements to uses of base::SmallMap

cc/scheduler/begin_frame_source.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 "cc/scheduler/begin_frame_source.h"
 
 #include <stddef.h>
 
 #include "base/atomic_sequence_num.h"
 #include "base/auto_reset.h"
@@ skipping 327 matching lines @@
   uint64_t latest_confirmed_sequence_number = current_sequence_number_;
   for (const auto& entry : latest_confirmed_sequence_numbers_) {
     latest_confirmed_sequence_number =
         std::min(latest_confirmed_sequence_number, entry.second);
   }
   return latest_confirmed_sequence_number;
 }
 
 void BeginFrameObserverAckTracker::AsValueInto(
     base::trace_event::TracedValue* state) const {
-  base::SmallMap<std::map<BeginFrameObserver*, uint64_t>, 4>
-      latest_confirmed_sequence_numbers_;
   state->SetInteger("current_source_id", current_source_id_);
   state->SetInteger("current_sequence_number", current_sequence_number_);
   state->SetInteger("num_observers", observers_.size());
   state->SetInteger("num_finished_observers", finished_observers_.size());
   state->SetBoolean("observers_had_damage", observers_had_damage_);
 
   state->BeginArray("latest_confirmed_sequence_numbers");
   for (const auto& kv : latest_confirmed_sequence_numbers_) {
     state->AppendInteger(kv.second);
   }
@@ skipping 120 matching lines @@
   frame_active_ = false;
 
   BeginFrameAck ack(last_begin_frame_args_.source_id,
                     last_begin_frame_args_.sequence_number,
                     ack_tracker_.LatestConfirmedSequenceNumber(),
                     ack_tracker_.AnyObserversHadDamage());
   client_->OnDidFinishFrame(ack);
 }
 
 }  // namespace cc