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

ui/events/event_utils.h

 // Copyright (c) 2012 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_EVENT_UTILS_H_
 #define UI_EVENTS_EVENT_UTILS_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 11 matching lines @@
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 
 namespace gfx {
 class Point;
 class Vector2d;
 }
 
 namespace base {
-class TimeDelta;
+class TimeTicks;
 }
 
 // Common functions to be used for all platforms except Android.
 namespace ui {
 
 class Event;
 class MouseEvent;
 enum class DomCode;
 
 // Returns a ui::Event wrapping a native event. Ownership of the returned value
 // is transferred to the caller.
 EVENTS_EXPORT std::unique_ptr<Event> EventFromNative(
     const base::NativeEvent& native_event);
 
 // Get the EventType from a native event.
 EVENTS_EXPORT EventType EventTypeFromNative(
     const base::NativeEvent& native_event);
 
 // Get the EventFlags from a native event.
 EVENTS_EXPORT int EventFlagsFromNative(const base::NativeEvent& native_event);
 
 // Get the timestamp from a native event.
 // Note: This is not a pure function meaning that multiple applications on the
 // same native event may return different values.
-EVENTS_EXPORT base::TimeDelta EventTimeFromNative(
+EVENTS_EXPORT base::TimeTicks EventTimeFromNative(
     const base::NativeEvent& native_event);
 
 // Create a timestamp based on the current time.
-EVENTS_EXPORT base::TimeDelta EventTimeForNow();
+// TODO(majidvp): Get rid of this in favor of call to TimeTicks::Now().
+// crbug.com/453559
+EVENTS_EXPORT base::TimeTicks EventTimeForNow();
 
 // Get the location from a native event.  The coordinate system of the resultant
 // |Point| has the origin at top-left of the "root window".  The nature of
 // this "root window" and how it maps to platform-specific drawing surfaces is
 // defined in ui/aura/root_window.* and ui/aura/window_tree_host*.
 // TODO(tdresser): Return gfx::PointF here. See crbug.com/337827.
 EVENTS_EXPORT gfx::Point EventLocationFromNative(
     const base::NativeEvent& native_event);
 
 // Gets the location in native system coordinate space.
@@ skipping 101 matching lines @@
 // Update the native X11 event to correspond to the new button flags.
 EVENTS_EXPORT void UpdateX11EventForChangedButtonFlags(MouseEvent* event);
 #endif
 
 // Registers a custom event type.
 EVENTS_EXPORT int RegisterCustomEventType();
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_EVENT_UTILS_H_