Quic: add unittests for reduced PING Timeout

net/quic/core/quic_connection.h

Index: net/quic/core/quic_connection.h
diff --git a/net/quic/core/quic_connection.h b/net/quic/core/quic_connection.h
index e4cb2f82735a714c98567178247ecffa5806e0e5..0af492fd43173e05cde5029741b96e2ca3843385 100644
--- a/net/quic/core/quic_connection.h
+++ b/net/quic/core/quic_connection.h
@@ -483,11 +483,13 @@ class NET_EXPORT_PRIVATE QuicConnection
     debug_visitor_ = debug_visitor;
     sent_packet_manager_->SetDebugDelegate(debug_visitor);
   }
+  // Used in Chromium, but not internally.

[Ryan Hamilton, 2016/09/02 21:26:52]

I'd just remove this comment.

[Zhongyi Shi, 2016/09/02 21:44:45]

This line is intentionally put there to note that this is not used internally,
and to keep the comments also in sync, it's needed here.

+  // Called only before ping_alarm_ is set.

[Ryan Hamilton, 2016/09/02 21:26:52]

nit: // Must only be called before ping_alarm_ is set.

(To make it clear that this is the contract, and not just a general description
of callers)

[Zhongyi Shi, 2016/09/02 21:44:45]

Done.

   void set_ping_timeout(QuicTime::Delta ping_timeout) {
+    DCHECK(!ping_alarm_->IsSet());
     ping_timeout_ = ping_timeout;
   }
   const QuicTime::Delta ping_timeout() { return ping_timeout_; }
-  // Used in Chromium, but not internally.
   void set_creator_debug_delegate(QuicPacketCreator::DebugDelegate* visitor) {
     packet_generator_.set_debug_delegate(visitor);
   }