Remove Timer

Now Timer is no longer used. Remove this.

This is part of efforts to replace default timer task runners with
other appropriate task runners in the renderer.

Bug: 624694, 804694
Change-Id: Ic0a0eccdfb9f98c0be8024d4f39a9c2b2ade5c9f
Reviewed-on: https://chromium-review.googlesource.com/926083Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Hajime Hoshi <hajimehoshi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537756}

third_party/WebKit/Source/platform/Timer.h

@@ -178,23 +178,6 @@ class TaskRunnerTimer : public TimerBase {
   TimerFiredFunction function_;
 };
 
-// TODO(dcheng): Consider removing this overload once all timers are using the
-// appropriate task runner. https://crbug.com/624694
-template <typename TimerFiredClass>
-class Timer : public TaskRunnerTimer<TimerFiredClass> {
- public:
-  using TimerFiredFunction =
-      typename TaskRunnerTimer<TimerFiredClass>::TimerFiredFunction;
-
-  ~Timer() override = default;
-
-  Timer(TimerFiredClass* timer_fired_class,
-        TimerFiredFunction timer_fired_function)
-      : TaskRunnerTimer<TimerFiredClass>(TimerBase::GetTimerTaskRunner(),
-                                         timer_fired_class,
-                                         timer_fired_function) {}
-};
-
 NO_SANITIZE_ADDRESS
 inline bool TimerBase::IsActive() const {
 #if DCHECK_IS_ON()