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..584300631bf4e4d079889c31d212b69c3555cb2b 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"
@@ -79,11 +80,9 @@ class GCM_EXPORT ConnectionFactoryImpl :
   net::IPEndPoint GetPeerIP();
 
  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.
@@ -112,11 +111,20 @@ class GCM_EXPORT ConnectionFactoryImpl :
   // ConnectionHandler callback for connection issues.
   void ConnectionHandlerCallback(int result);
 
+  // The tracker will maintain a list of all connection attempts with GCM,
+  // whether they suceeded, and their duration.
+  ConnectionEventTracker event_tracker_;

[Nicolas Zea, 2016/12/01 18:51:49]

nit: protected members are kind of discouraged. I think it would be cleaner to
just inject this in at construction time if you want access to it in a test.

[Peter Beverloo, 2016/12/02 15:19:13]

+1 (our C++ style guide outright forbids this except for testing)

[harkness, 2016/12/05 15:39:01]

Moved it and added a ForTesting accessor.

+
  private:
   // Helper method for checking backoff and triggering a connection as
   // necessary.
   void ConnectWithBackoff();
 
+  // Implementation of Connect(..). If not in backoff, uses |login_request_|
+  // 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);