Improvements to uses of base::SmallMap

cc/scheduler/begin_frame_source.cc

Index: cc/scheduler/begin_frame_source.cc
diff --git a/cc/scheduler/begin_frame_source.cc b/cc/scheduler/begin_frame_source.cc
index 36e3a62aa055b57b6ba52d9ef6576e4d6824d3ba..1687eeddf7a01c09ff73eff430cc926cc4d2592c 100644
--- a/cc/scheduler/begin_frame_source.cc
+++ b/cc/scheduler/begin_frame_source.cc
@@ -345,7 +345,7 @@ uint64_t BeginFrameObserverAckTracker::LatestConfirmedSequenceNumber() const {
 
 void BeginFrameObserverAckTracker::AsValueInto(
     base::trace_event::TracedValue* state) const {
-  base::SmallMap<std::map<BeginFrameObserver*, uint64_t>, 4>
+  base::small_map<std::map<BeginFrameObserver*, uint64_t>, 4>

[danakj, 2017/04/18 21:35:50]

do my eyes deceive me or is this shadowing the member variable with a local of
the same name that will be empty?

[brettw, 2017/04/19 16:29:48]

That's nuts. I'll fix it, hopefully I don't break anything.

       latest_confirmed_sequence_numbers_;
   state->SetInteger("current_source_id", current_source_id_);
   state->SetInteger("current_sequence_number", current_sequence_number_);