Type conversion fixes, media/ edition.

media/cast/cast_defines.h

 // Copyright 2013 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.
 
 #ifndef MEDIA_CAST_CAST_DEFINES_H_
 #define MEDIA_CAST_CAST_DEFINES_H_
 
 #include <stdint.h>
 
+#include <cmath>
 #include <map>
 #include <set>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/time/time.h"
 #include "media/cast/net/cast_transport_config.h"
 
 namespace media {
@@ skipping 151 matching lines @@
 
   int64 ntp_time_us =
       elapsed_since_unix_epoch.InMicroseconds() +
       (kUnixEpochInNtpSeconds * base::Time::kMicrosecondsPerSecond);
 
   ConvertTimeToFractions(ntp_time_us, ntp_seconds, ntp_fractions);
 }
 
 inline base::TimeTicks ConvertNtpToTimeTicks(uint32 ntp_seconds,
                                              uint32 ntp_fractions) {
-  int64 ntp_time_us =
-      static_cast<int64>(ntp_seconds) * base::Time::kMicrosecondsPerSecond +
-      static_cast<int64>(ntp_fractions) / kMagicFractionalUnit;
+  // We need to ceil() here because the calculation of |fractions| in
+  // ConvertTimeToFractions() effectively does a floor().
+  int64 ntp_time_us = ntp_seconds * base::Time::kMicrosecondsPerSecond +
+      static_cast<int64>(std::ceil(ntp_fractions / kMagicFractionalUnit));
 
   base::TimeDelta elapsed_since_unix_epoch = base::TimeDelta::FromMicroseconds(
       ntp_time_us -
       (kUnixEpochInNtpSeconds * base::Time::kMicrosecondsPerSecond));
   return base::TimeTicks::UnixEpoch() + elapsed_since_unix_epoch;
 }
 
 inline base::TimeDelta RtpDeltaToTimeDelta(int64 rtp_delta, int rtp_timebase) {
   DCHECK_GT(rtp_timebase, 0);
   return rtp_delta * base::TimeDelta::FromSeconds(1) / rtp_timebase;
 }
 
 inline int64 TimeDeltaToRtpDelta(base::TimeDelta delta, int rtp_timebase) {
   DCHECK_GT(rtp_timebase, 0);
   return delta * rtp_timebase / base::TimeDelta::FromSeconds(1);
 }
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_CAST_DEFINES_H_