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

ui/events/blink/blink_event_util_unittest.cc

 // Copyright 2016 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/blink/blink_event_util.h"
 
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "ui/events/gesture_event_details.h"
 
 namespace ui {
 
 using BlinkEventUtilTest = testing::Test;
 
 TEST(BlinkEventUtilTest, NoScalingWith1DSF) {
   const ui::GestureEventDetails details(ui::ET_GESTURE_SCROLL_UPDATE,
                                         1,
                                         1);
   auto event =
       CreateWebGestureEvent(details,
-                            base::TimeDelta::FromMilliseconds(1),
+                            base::TimeTicks(),
                             gfx::PointF(1.f, 1.f),
                             gfx::PointF(1.f, 1.f),
                             0);
   EXPECT_FALSE(ScaleWebInputEvent(event, 1.f));
   EXPECT_TRUE(ScaleWebInputEvent(event, 2.f));
 }
 
 }  // namespace ui