Added ClientEvent proto and structure for storing events in the factory.

google_apis/gcm/engine/connection_factory_impl.h

Index: google_apis/gcm/engine/connection_factory_impl.h
diff --git a/google_apis/gcm/engine/connection_factory_impl.h b/google_apis/gcm/engine/connection_factory_impl.h
index 04c5e4f9c4b3b9b0085269b4ac573fc613b6d3d5..e800513738218fd6db62b040a3f7bf4dbd61c428 100644
--- a/google_apis/gcm/engine/connection_factory_impl.h
+++ b/google_apis/gcm/engine/connection_factory_impl.h
@@ -12,6 +12,7 @@
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
+#include "google_apis/gcm/engine/connection_event_tracker.h"
 #include "google_apis/gcm/engine/connection_handler.h"
 #include "google_apis/gcm/protocol/mcs.pb.h"
 #include "net/base/backoff_entry.h"
@@ -78,12 +79,14 @@ class GCM_EXPORT ConnectionFactoryImpl :
   // connection is active, returns an empty IPEndpoint.
   net::IPEndPoint GetPeerIP();
 
+  ConnectionEventTracker* GetEventTrackerForTesting() {

[Peter Beverloo, 2016/12/05 16:29:35]

nit: prefer making this private w/ a friends declaration

[harkness, 2016/12/06 12:53:35]

Done.

+    return &event_tracker_;
+  }
+
  protected:
-  // Implementation of Connect(..). If not in backoff, uses |login_request_|
-  // in attempting a connection/handshake. On connection/handshake failure, goes
-  // into backoff.
+  // Initiate the connection to the GCM server.
   // Virtual for testing.
-  virtual void ConnectImpl();
+  virtual void StartConnection();
 
   // Helper method for initalizing the connection hander.
   // Virtual for testing.
@@ -117,6 +120,11 @@ class GCM_EXPORT ConnectionFactoryImpl :
   // necessary.
   void ConnectWithBackoff();
 
+  // Implementation of Connect(..). If not in backoff, uses |login_request_|

[Peter Beverloo, 2016/12/05 16:29:35]

nit: |login_request_| does not exist. Mind updating the comment?

[harkness, 2016/12/06 12:53:35]

Done.

+  // in attempting a connection/handshake. On connection/handshake failure, goes
+  // into backoff.
+  void ConnectImpl();
+
   // Proxy resolution and connection functions.
   void OnProxyResolveDone(int status);
   void OnProxyConnectDone(int status);
@@ -130,6 +138,10 @@ class GCM_EXPORT ConnectionFactoryImpl :
   // Session's cache, if available.
   void RebuildNetworkSessionAuthCache();
 
+  // The tracker will maintain a list of all connection attempts with GCM,
+  // whether they suceeded, and their duration.

[Peter Beverloo, 2016/12/05 16:29:35]

nit: s/suceeded/succeeded/

[harkness, 2016/12/06 12:53:35]

Done.

+  ConnectionEventTracker event_tracker_;
+
   // The MCS endpoints to make connections to, sorted in order of priority.
   const std::vector<GURL> mcs_endpoints_;
   // Index to the endpoint for which a connection should be attempted next.