Fix more disabled MSVC warnings, base/ edition.

base/time/time.h

 // 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.
 
 // Time represents an absolute point in coordinated universal time (UTC),
 // internally represented as microseconds (s/1,000,000) since the Windows epoch
 // (1601-01-01 00:00:00 UTC) (See http://crbug.com/14734).  System-dependent
 // clock interface routines are defined in time_PLATFORM.cc.
 //
 // TimeDelta represents a duration of time, internally represented in
@@ skipping 520 matching lines @@
   if (ms == std::numeric_limits<int64>::max())
     return Max();
   return TimeDelta(ms * Time::kMicrosecondsPerMillisecond);
 }
 
 // static
 inline TimeDelta TimeDelta::FromSecondsD(double secs) {
   // Preserve max to prevent overflow.
   if (secs == std::numeric_limits<double>::infinity())
     return Max();
-  return TimeDelta(secs * Time::kMicrosecondsPerSecond);
+  return TimeDelta(static_cast<int64>(secs * Time::kMicrosecondsPerSecond));
 }
 
 // static
 inline TimeDelta TimeDelta::FromMillisecondsD(double ms) {
   // Preserve max to prevent overflow.
   if (ms == std::numeric_limits<double>::infinity())
     return Max();
-  return TimeDelta(ms * Time::kMicrosecondsPerMillisecond);
+  return TimeDelta(static_cast<int64>(ms * Time::kMicrosecondsPerMillisecond));
 }
 
 // static
 inline TimeDelta TimeDelta::FromMicroseconds(int64 us) {
   // Preserve max to prevent overflow.
   if (us == std::numeric_limits<int64>::max())
     return Max();
   return TimeDelta(us);
 }
 
@@ skipping 159 matching lines @@
 #endif
 };
 
 inline TimeTicks TimeDelta::operator+(TimeTicks t) const {
   return TimeTicks(t.ticks_ + delta_);
 }
 
 }  // namespace base
 
 #endif  // BASE_TIME_TIME_H_