Change QUIC's pacing granularity from 5ms to 1ms to match the kernel's

net/quic/quic_sent_packet_manager.cc

Index: net/quic/quic_sent_packet_manager.cc
diff --git a/net/quic/quic_sent_packet_manager.cc b/net/quic/quic_sent_packet_manager.cc
index 3e81e747890815db0a374a20670694f8cb8341d8..b9c8d22c8a06fea3e3c89f3a21997a895026f042 100644
--- a/net/quic/quic_sent_packet_manager.cc
+++ b/net/quic/quic_sent_packet_manager.cc
@@ -873,11 +873,12 @@ void QuicSentPacketManager::EnablePacing() {
     return;
   }
 
-  // Set up a pacing sender with a 5 millisecond alarm granularity.
+  // Set up a pacing sender with a 1 millisecond alarm granularity, the same as
+  // the default granularity of the Linux kernel's FQ qdisc.
   using_pacing_ = true;
   send_algorithm_.reset(
       new PacingSender(send_algorithm_.release(),
-                       QuicTime::Delta::FromMilliseconds(5),
+                       QuicTime::Delta::FromMilliseconds(1),
                        kInitialUnpacedBurst));
 }