Change ui::Event::time_stamp from TimeDelta to TimeTicks

ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.h

 // Copyright 2015 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.
 
 #ifndef UI_EVENTS_OZONE_EVDEV_TOUCH_NOISE_FAR_APART_TAPS_TOUCH_NOISE_FILTER_H_
 #define UI_EVENTS_OZONE_EVDEV_TOUCH_NOISE_FAR_APART_TAPS_TOUCH_NOISE_FILTER_H_
 
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "ui/events/ozone/evdev/touch_noise/touch_noise_filter.h"
 
 namespace ui {
 
 class FarApartTapsTouchNoiseFilter : public TouchNoiseFilter {
  public:
   FarApartTapsTouchNoiseFilter() {}
   ~FarApartTapsTouchNoiseFilter() override {}
 
   // TouchNoiseFilter:
   void Filter(const std::vector<InProgressTouchEvdev>& touches,
-              base::TimeDelta time,
+              base::TimeTicks time,
               std::bitset<kNumTouchEvdevSlots>* slots_with_noise) override;
 
  private:
   struct Tap {
     Tap() : x(0), y(0) {}
-    Tap(base::TimeDelta start, int x, int y)
+    Tap(base::TimeTicks start, int x, int y)
         : start(start), x(x), y(y) {}
 
-    bool is_valid() const { return !start.is_zero(); }
-    void Invalidate() { start = base::TimeDelta(); }
+    bool is_valid() const { return start != base::TimeTicks(); }

[miu, 2016/05/16 20:05:35]

!start.is_null()

[majidvp, 2016/05/21 01:38:00]

Done.

+    void Invalidate() { start = base::TimeTicks(); }
 
-    base::TimeDelta start;
+    base::TimeTicks start;
     float x;
     float y;
   };
 
   // Tracks in progress taps in slots.
   Tap tracked_taps_[kNumTouchEvdevSlots];
 
   DISALLOW_COPY_AND_ASSIGN(FarApartTapsTouchNoiseFilter);
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_OZONE_EVDEV_TOUCH_NOISE_FAR_APART_TAPS_TOUCH_NOISE_FILTER_H_