Change base::TickClock to a ref counted class.

ui/events/test/event_generator.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 "ui/events/test/event_generator.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 465 matching lines @@
 }
 
 void EventGenerator::ReleaseKey(ui::KeyboardCode key_code, int flags) {
   DispatchKeyEvent(false, key_code, flags);
 }
 
 void EventGenerator::Dispatch(ui::Event* event) {
   DoDispatchEvent(event, async_);
 }
 
-void EventGenerator::SetTickClock(scoped_ptr<base::TickClock> tick_clock) {
-  tick_clock_ = tick_clock.Pass();
+void EventGenerator::SetTickClock(
+    const scoped_refptr<base::TickClock>& tick_clock) {
+  tick_clock_ = tick_clock;
 }
 
 base::TimeDelta EventGenerator::Now() {
   // This is the same as what EventTimeForNow() does, but here we do it
   // with a tick clock that can be replaced with a simulated clock for tests.
   return base::TimeDelta::FromInternalValue(
       tick_clock_->NowTicks().ToInternalValue());
 }
 
 void EventGenerator::Init(gfx::NativeWindow root_window,
@@ skipping 125 matching lines @@
   return default_delegate;
 }
 
 EventGeneratorDelegate* EventGenerator::delegate() {
   return const_cast<EventGeneratorDelegate*>(
       const_cast<const EventGenerator*>(this)->delegate());
 }
 
 }  // namespace test
 }  // namespace ui