Land Recent QUIC changes.

net/quic/quic_time.h

Index: net/quic/quic_time.h
diff --git a/net/quic/quic_time.h b/net/quic/quic_time.h
index 067027befc326c95ebea7fd616a9c03da34673f0..9c846c9be264400a7dea63e1a02f3a72633edfdd 100644
--- a/net/quic/quic_time.h
+++ b/net/quic/quic_time.h
@@ -108,6 +108,10 @@ class NET_EXPORT_PRIVATE QuicWallTime {
   // since the UNIX epoch.
   static QuicWallTime FromUNIXSeconds(uint64 seconds);
 
+  // Zero returns a QuicWallTime set to zero. IsZero will return true for this
+  // value.
+  static QuicWallTime Zero();
+
   // ToUNIXSeconds converts a QuicWallTime into a count of seconds since the
   // UNIX epoch.
   uint64 ToUNIXSeconds() const;
@@ -115,6 +119,9 @@ class NET_EXPORT_PRIVATE QuicWallTime {
   bool IsAfter(QuicWallTime other) const;
   bool IsBefore(QuicWallTime other) const;
 
+  // IsZero returns true if this object is the result of calling |Zero|.
+  bool IsZero() const;
+
   // AbsoluteDifference returns the absolute value of the time difference
   // between |this| and |other|.
   QuicTime::Delta AbsoluteDifference(QuicWallTime other) const;