Use overloaded operators with QuicTime for addition, subtraction and scalar

net/quic/congestion_control/hybrid_slow_start_test.cc

 // Copyright (c) 2012 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 "net/quic/congestion_control/hybrid_slow_start.h"
 
 #include <memory>
 
 #include "base/logging.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 41 matching lines @@
   // RTT of 60ms the detection will happen at 67.5 ms.
   const int kHybridStartMinSamples = 8;  // Number of acks required to trigger.
 
   QuicPacketNumber end_packet_number = 1;
   slow_start_->StartReceiveRound(end_packet_number++);
 
   // Will not trigger since our lowest RTT in our burst is the same as the long
   // term RTT provided.
   for (int n = 0; n < kHybridStartMinSamples; ++n) {
     EXPECT_FALSE(slow_start_->ShouldExitSlowStart(
-        rtt_.Add(QuicTime::Delta::FromMilliseconds(n)), rtt_, 100));
+        rtt_ + QuicTime::Delta::FromMilliseconds(n), rtt_, 100));
   }
   slow_start_->StartReceiveRound(end_packet_number++);
   for (int n = 1; n < kHybridStartMinSamples; ++n) {
     EXPECT_FALSE(slow_start_->ShouldExitSlowStart(
-        rtt_.Add(QuicTime::Delta::FromMilliseconds(n + 10)), rtt_, 100));
+        rtt_ + QuicTime::Delta::FromMilliseconds(n + 10), rtt_, 100));
   }
   // Expect to trigger since all packets in this burst was above the long term
   // RTT provided.
   EXPECT_TRUE(slow_start_->ShouldExitSlowStart(
-      rtt_.Add(QuicTime::Delta::FromMilliseconds(10)), rtt_, 100));
+      rtt_ + QuicTime::Delta::FromMilliseconds(10), rtt_, 100));
 }
 
 }  // namespace test
 }  // namespace net