Fix Integer-overflow in base::Time::FromExploded.

base/time/time.h

Index: base/time/time.h
diff --git a/base/time/time.h b/base/time/time.h
index 12e43d9e7a02cf52711684f389a49ac5e51237f2..286c0738ceb4522f791a9d9cd4ac1c67f2472ae2 100644
--- a/base/time/time.h
+++ b/base/time/time.h
@@ -545,7 +545,7 @@ class BASE_EXPORT Time : public time_internal::TimeBase<Time> {
 
   // Converts an exploded structure representing either the local time or UTC
   // into a Time class. Returns false on a failure when, for example, a day of
-  // month is set to 31 on a 28-30 day month.
+  // month is set to 31 on a 28-30 day month. Returns Time(0) on overflow.
   static bool FromUTCExploded(const Exploded& exploded,
                               Time* time) WARN_UNUSED_RESULT {
     return FromExploded(false, exploded, time);