Add instrumentation to track the IceEndpointType.

talk/app/webrtc/fakemetricsobserver.h

Index: talk/app/webrtc/fakemetricsobserver.h
diff --git a/talk/app/webrtc/fakemetricsobserver.h b/talk/app/webrtc/fakemetricsobserver.h
index e9e49749bf104246b32dab0d3ebc124cc355cd2b..c1e1e32c1d7b384282e97a38bc568b609679cb83 100644
--- a/talk/app/webrtc/fakemetricsobserver.h
+++ b/talk/app/webrtc/fakemetricsobserver.h
@@ -41,14 +41,16 @@ class FakeMetricsObserver : public MetricsObserverInterface {
   FakeMetricsObserver();
   void Reset();
 
-  void IncrementCounter(PeerConnectionMetricsCounter type) override;
+  void IncrementEnumCounter(PeerConnectionEnumCounterType,
+                            int counter,
+                            int counter_max) override;
   void AddHistogramSample(PeerConnectionMetricsName type,
                           int value) override;
   void AddHistogramSample(PeerConnectionMetricsName type,
                           const std::string& value) override;
 
   // Accessors to be used by the tests.
-  int GetCounter(PeerConnectionMetricsCounter type) const;
+  int GetCounter(PeerConnectionEnumCounterType type, int counter) const;

[pthatcher1, 2015/08/18 18:06:22]

If you renamed one to IncrementEnumCounter, shouldn't you rename the other to
GetEnumCounter?

[guoweis_webrtc, 2015/08/18 22:33:57]

Done.

   int GetIntHistogramSample(PeerConnectionMetricsName type) const;
   const std::string& GetStringHistogramSample(
       PeerConnectionMetricsName type) const;
@@ -58,8 +60,8 @@ class FakeMetricsObserver : public MetricsObserverInterface {
 
  private:
   rtc::ThreadChecker thread_checker_;
-  int counters_[kPeerConnectionMetricsCounter_Max];
-  int int_histogram_samples_[kPeerConnectionMetricsCounter_Max];
+  std::vector<std::vector<int>> counters_;

[pthatcher1, 2015/08/18 18:06:22]

Can you put a comment about what the indexes are (I'm assuming enum type, and
then counter, but a comment would help out).

[guoweis_webrtc, 2015/08/18 22:33:57]

Done.

+  int int_histogram_samples_[kPeerConnectionMetricsName_Max];

[pthatcher1, 2015/08/18 18:06:22]

It seems like you should have an array of vectors in counters_ or a a vector in
int_histogram_samples_ to make them consistent. 

[guoweis_webrtc, 2015/08/18 22:33:57]

histogram_samples use string to track each sample so they don't need this.

   std::string string_histogram_samples_[kPeerConnectionMetricsName_Max];
 };