Update from https://crrev.com/333737

cc/debug/lap_timer.cc

 // Copyright 2014 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.
 
 #include "cc/debug/lap_timer.h"
 
 #include "base/logging.h"
 
 namespace cc {
 
 namespace {
 
-base::TimeTicks Now() {
-  return base::TimeTicks::IsThreadNowSupported() ? base::TimeTicks::ThreadNow()
-                                                 : base::TimeTicks::Now();
+base::TimeDelta Now() {
+  return base::ThreadTicks::IsSupported()
+             ? base::ThreadTicks::Now() - base::ThreadTicks()
+             : base::TimeTicks::Now() - base::TimeTicks();
 }
 
 }  // namespace
 
 LapTimer::LapTimer(int warmup_laps,
                    base::TimeDelta time_limit,
                    int check_interval)
     : warmup_laps_(warmup_laps),
       remaining_warmups_(0),
       remaining_no_check_laps_(0),
@@ skipping 21 matching lines @@
   if (!IsWarmedUp()) {
     --remaining_warmups_;
     if (IsWarmedUp()) {
       Start();
     }
     return;
   }
   ++num_laps_;
   --remaining_no_check_laps_;
   if (!remaining_no_check_laps_) {
-    base::TimeTicks now = Now();
+    base::TimeDelta now = Now();
     accumulator_ += now - start_time_;
     start_time_ = now;
     remaining_no_check_laps_ = check_interval_;
   }
 }
 
 bool LapTimer::HasTimeLimitExpired() { return accumulator_ >= time_limit_; }
 
 bool LapTimer::HasTimedAllLaps() { return !(num_laps_ % check_interval_); }
 
 float LapTimer::MsPerLap() {
   DCHECK(HasTimedAllLaps());
   return accumulator_.InMillisecondsF() / num_laps_;
 }
 
 float LapTimer::LapsPerSecond() {
   DCHECK(HasTimedAllLaps());
   return num_laps_ / accumulator_.InSecondsF();
 }
 
 int LapTimer::NumLaps() { return num_laps_; }
 
 }  // namespace cc