Update ConnectionEventTracker to check if there is an in progress attempt.

google_apis/gcm/engine/connection_factory_impl_unittest.cc

 // Copyright (c) 2013 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 "google_apis/gcm/engine/connection_factory_impl.h"
 
 #include <cmath>
 #include <utility>
 
 #include "base/memory/ptr_util.h"
@@ skipping 584 matching lines @@
   const int kNumAttempts = 50;
   factory()->SetMultipleConnectResults(net::ERR_CONNECTION_FAILED,
                                        kNumAttempts);
 
   factory()->Connect();
   WaitForConnections();
 
   // There should be one failed client event for each failed connection, but
   // there is a maximum cap of kMaxClientEvents, which is 30. There should also
   // be a single event which records the events which were discarded.
-  const auto client_events = GetClientEvents();
+  auto client_events = GetClientEvents();
   ASSERT_EQ(31, client_events.size());
 
   bool found_discarded_events = false;
   for (const auto& client_event : client_events) {
     if (client_event.type() == mcs_proto::ClientEvent::DISCARDED_EVENTS) {
       // There should only be one event for discarded events.
       EXPECT_FALSE(found_discarded_events);
       found_discarded_events = true;
       // There should be 50-30=20 discarded events.
       EXPECT_EQ(20U, client_event.number_discarded_events());
     } else {
       EXPECT_EQ(mcs_proto::ClientEvent::FAILED_CONNECTION, client_event.type());
       EXPECT_EQ(net::ERR_CONNECTION_FAILED, client_event.error_code());
     }
   }
   EXPECT_TRUE(found_discarded_events);
 
   factory()->SetConnectResult(net::OK);
   WaitForConnections();
   EXPECT_TRUE(factory()->IsEndpointReachable());
   EXPECT_TRUE(connected_server().is_valid());
 
   // Old client events should have been reset after the successful connection.
-  const auto new_client_events = GetClientEvents();
-  ASSERT_EQ(0, new_client_events.size());
+  client_events = GetClientEvents();
+  ASSERT_EQ(0, client_events.size());
+
+  // Test that EndConnectionAttempt doesn't write empty events to the tracker.
+  // There should be 2 events: 1) the successful connection which was previously
+  // established. 2) the unsuccessful connection triggered as a result of the
+  // SOCKET_FAILURE signal. The NETWORK_CHANGE signal should not cause an
+  // additional event since there is no in progress event.
+  factory()->SetConnectResult(net::ERR_CONNECTION_FAILED);
+  factory()->SignalConnectionReset(ConnectionFactory::SOCKET_FAILURE);
+  factory()->SignalConnectionReset(ConnectionFactory::NETWORK_CHANGE);
+  WaitForConnections();
+
+  client_events = GetClientEvents();
+  ASSERT_EQ(2, client_events.size());
 }
 
 }  // namespace gcm