Fix more swarming test failures by using fake clock.

webrtc/p2p/base/port.cc

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 907 matching lines @@
   WriteState old_value = write_state_;
   write_state_ = value;
   if (value != old_value) {
     LOG_J(LS_VERBOSE, this) << "set_write_state from: " << old_value << " to "
                             << value;
     SignalStateChange(this);
   }
 }
 
 void Connection::UpdateReceiving(int64_t now) {
-  bool receiving = now <= last_received() + receiving_timeout_;
+  bool receiving =
+      last_received() > 0 && now <= last_received() + receiving_timeout_;
   if (receiving_ == receiving) {
     return;
   }
   LOG_J(LS_VERBOSE, this) << "set_receiving to " << receiving;
   receiving_ = receiving;
   receiving_unchanged_since_ = now;
   SignalStateChange(this);
 }
 
 void Connection::set_state(State state) {
@@ skipping 631 matching lines @@
     ASSERT(sent < 0);
     error_ = port_->GetError();
     stats_.sent_discarded_packets++;
   } else {
     send_rate_tracker_.AddSamples(sent);
   }
   return sent;
 }
 
 }  // namespace cricket