Add an Update method on QuicAlarm which contains a granularity. Also

net/tools/quic/quic_epoll_connection_helper_test.cc

Index: net/tools/quic/quic_epoll_connection_helper_test.cc
diff --git a/net/tools/quic/quic_epoll_connection_helper_test.cc b/net/tools/quic/quic_epoll_connection_helper_test.cc
index 0f977f4fb305f5d620e089a4d0a283ecc60a7c5a..708bdd4b6b0672e0a858257e97a994e4ba4619be 100644
--- a/net/tools/quic/quic_epoll_connection_helper_test.cc
+++ b/net/tools/quic/quic_epoll_connection_helper_test.cc
@@ -103,6 +103,42 @@ TEST_F(QuicEpollConnectionHelperTest, CreateAlarmAndReset) {
   EXPECT_TRUE(delegate->fired());
 }
 
+TEST_F(QuicEpollConnectionHelperTest, CreateAlarmAndUpdate) {
+  TestDelegate* delegate = new TestDelegate();
+  scoped_ptr<QuicAlarm> alarm(helper_.CreateAlarm(delegate));
+
+  const QuicClock* clock = helper_.GetClock();
+  QuicTime start = clock->Now();
+  QuicTime::Delta delta = QuicTime::Delta::FromMicroseconds(1);
+  alarm->Set(clock->Now().Add(delta));
+  QuicTime::Delta new_delta = QuicTime::Delta::FromMicroseconds(3);
+  alarm->Update(clock->Now().Add(new_delta),
+                QuicTime::Delta::FromMicroseconds(1));
+
+  epoll_server_.AdvanceByExactlyAndCallCallbacks(delta.ToMicroseconds());
+  EXPECT_EQ(start.Add(delta), clock->Now());
+  EXPECT_FALSE(delegate->fired());
+
+  // Move the alarm forward 1us and ensure it doesn't move forward.
+  alarm->Update(clock->Now().Add(new_delta),
+                QuicTime::Delta::FromMicroseconds(2));
+
+  epoll_server_.AdvanceByExactlyAndCallCallbacks(
+      new_delta.Subtract(delta).ToMicroseconds());
+  EXPECT_EQ(start.Add(new_delta), clock->Now());
+  EXPECT_TRUE(delegate->fired());
+
+  // Set the alarm via an update call.
+  new_delta = QuicTime::Delta::FromMicroseconds(5);
+  alarm->Update(clock->Now().Add(new_delta),
+                QuicTime::Delta::FromMicroseconds(1));
+  EXPECT_TRUE(alarm->IsSet());
+
+  // Update it with an uninitialized time and ensure it's cancelled.
+  alarm->Update(QuicTime::Zero(), QuicTime::Delta::FromMicroseconds(1));
+  EXPECT_FALSE(alarm->IsSet());
+}
+
 }  // namespace
 }  // namespace test
 }  // namespace tools