Set the unique_event_id when converting from TouchEvent to WebTouchEvent

components/html_viewer/touch_handler.cc

 // 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.
 
 #include "components/html_viewer/touch_handler.h"
 
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "third_party/WebKit/public/web/WebView.h"
+#include "ui/events/base_event_utils.h"
 #include "ui/events/blink/blink_event_util.h"
 #include "ui/events/gesture_detection/gesture_provider_config_helper.h"
 #include "ui/events/gesture_detection/motion_event_generic.h"
 #include "ui/mojo/events/input_events.mojom.h"
 
 namespace html_viewer {
 namespace {
 
 void SetPropertiesFromEvent(const mojo::Event& event,
                             ui::PointerProperties* properties) {
@@ skipping 44 matching lines @@
   web_view_->handleInputEvent(web_gesture);
 }
 
 bool TouchHandler::UpdateMotionEvent(const mojo::Event& event) {
   ui::PointerProperties properties;
   SetPropertiesFromEvent(event, &properties);
 
   const base::TimeTicks timestamp(
       base::TimeTicks::FromInternalValue(event.time_stamp));
   if (current_motion_event_.get()) {
-    current_motion_event_->set_id(current_motion_event_->GetId() + 1);
+    current_motion_event_->set_unique_event_id(ui::GetNextTouchEventId());
     current_motion_event_->set_event_time(timestamp);
   }
 
   switch (event.action) {
     case mojo::EVENT_TYPE_POINTER_DOWN:
       if (!current_motion_event_.get()) {
         current_motion_event_.reset(new ui::MotionEventGeneric(
             ui::MotionEvent::ACTION_DOWN, timestamp, properties));
       } else {
         const int index =
@@ skipping 94 matching lines @@
     case mojo::EVENT_TYPE_POINTER_CANCEL:
       current_motion_event_.reset();
       break;
 
     default:
       break;
   }
 }
 
 }  // namespace html_viewer