Remove unnecessary mocking of TickClock for events

ui/events/test/event_generator.h

Index: ui/events/test/event_generator.h
diff --git a/ui/events/test/event_generator.h b/ui/events/test/event_generator.h
index 46f1569dcea675b184c8e6116897e6a5d9889480..a05a37937790a9faeb90cc8d2dc7b8018b612018 100644
--- a/ui/events/test/event_generator.h
+++ b/ui/events/test/event_generator.h
@@ -367,12 +367,6 @@ class EventGenerator {
     current_target_ = target;
   }
 
-  // Specify an alternative tick clock to be used for simulating time in tests.
-  void SetTickClock(std::unique_ptr<base::TickClock> tick_clock);
-
-  // Get the current time from the tick clock.
-  base::TimeTicks Now();
-
   // Default delegate set by a platform-specific GeneratorDelegate singleton.
   static EventGeneratorDelegate* default_delegate;