Simplify ScheduleDelayedWork implementation on Mac

base/message_pump_mac.mm

 // 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.
 
 #import "base/message_pump_mac.h"
 
 #import <AppKit/AppKit.h>
 #import <Foundation/Foundation.h>
 
 #include <limits>
@@ skipping 174 matching lines @@
 
 // May be called on any thread.
 void MessagePumpCFRunLoopBase::ScheduleWork() {
   CFRunLoopSourceSignal(work_source_);
   CFRunLoopWakeUp(run_loop_);
 }
 
 // Must be called on the run loop thread.
 void MessagePumpCFRunLoopBase::ScheduleDelayedWork(
     const TimeTicks& delayed_work_time) {
-  // TODO(jar): We may need a more efficient way to go between these times, but
-  // the difference will change not only when we sleep/wake, it will also change
-  // when the user changes the wall clock time :-/.
-  Time absolute_work_time =
-      (delayed_work_time - TimeTicks::Now()) + Time::Now();
-
-  Time::Exploded exploded;
-  absolute_work_time.UTCExplode(&exploded);
-  double seconds = exploded.second +
-                   (static_cast<double>((absolute_work_time.ToInternalValue()) %
-                                        Time::kMicrosecondsPerSecond) /
-                    Time::kMicrosecondsPerSecond);
-  CFGregorianDate gregorian = {
-    exploded.year,
-    exploded.month,
-    exploded.day_of_month,
-    exploded.hour,
-    exploded.minute,
-    seconds
-  };
-  delayed_work_fire_time_ = CFGregorianDateGetAbsoluteTime(gregorian, NULL);
-
+  TimeDelta delta = delayed_work_time - TimeTicks::Now();
+  delayed_work_fire_time_ = CFAbsoluteTimeGetCurrent() + delta.InSecondsF();
   CFRunLoopTimerSetNextFireDate(delayed_work_timer_, delayed_work_fire_time_);
 }
 
 // Called from the run loop.
 // static
 void MessagePumpCFRunLoopBase::RunDelayedWorkTimer(CFRunLoopTimerRef timer,
                                                    void* info) {
   MessagePumpCFRunLoopBase* self = static_cast<MessagePumpCFRunLoopBase*>(info);
 
   // The timer won't fire again until it's reset.
@@ skipping 446 matching lines @@
 }
 
 // static
 bool MessagePumpMac::IsHandlingSendEvent() {
   DCHECK([NSApp conformsToProtocol:@protocol(CrAppProtocol)]);
   NSObject<CrAppProtocol>* app = static_cast<NSObject<CrAppProtocol>*>(NSApp);
   return [app isHandlingSendEvent];
 }
 
 }  // namespace base