Coalesce async touch move events until the ack back from render

content/common/input/web_input_event_traits.cc

 // Copyright 2013 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 "content/common/input/web_input_event_traits.h"
 
 #include <bitset>
 #include <limits>
 
 #include "base/logging.h"
@@ skipping 92 matching lines @@
   point.radiusX,
   point.radiusY,
   point.rotationAngle,
   point.force);
 }
 
 void ApppendEventDetails(const WebTouchEvent& event, std::string* result) {
   StringAppendF(result,
                 "{\n Touches: %u, Cancelable: %d, CausesScrolling: %d,"
                 " uniqueTouchEventId: %u\n[\n",
-                event.touchesLength,
-                event.cancelable,
-                event.causesScrollingIfUncanceled,
-                static_cast<uint32>(event.uniqueTouchEventId));
+                event.touchesLength, event.cancelable,
+                event.causesScrollingIfUncanceled, event.uniqueTouchEventId);
   for (unsigned i = 0; i < event.touchesLength; ++i)
     ApppendTouchPointDetails(event.touches[i], result);
   result->append(" ]\n}");
 }
 
 bool CanCoalesce(const WebKeyboardEvent& event_to_coalesce,
                  const WebKeyboardEvent& event) {
   return false;
 }
 
@@ skipping 329 matching lines @@
                event_to_coalesce,
                &event);
 }
 
 void WebInputEventTraits::Coalesce(const WebInputEvent& event_to_coalesce,
                                    WebInputEvent* event) {
   DCHECK(event);
   Apply(WebInputEventCoalesce(), event->type, event_to_coalesce, event);
 }
 
-bool WebInputEventTraits::IgnoresAckDisposition(const WebInputEvent& event) {
+bool WebInputEventTraits::WillReceiveAckFromRenderer(
+    const WebInputEvent& event) {
   switch (event.type) {
     case WebInputEvent::MouseDown:
     case WebInputEvent::MouseUp:
     case WebInputEvent::MouseEnter:
     case WebInputEvent::MouseLeave:
     case WebInputEvent::ContextMenu:
     case WebInputEvent::GestureScrollBegin:
     case WebInputEvent::GestureScrollEnd:
     case WebInputEvent::GestureShowPress:
     case WebInputEvent::GestureTapUnconfirmed:
     case WebInputEvent::GestureTapDown:
     case WebInputEvent::GestureTapCancel:
     case WebInputEvent::GesturePinchBegin:
     case WebInputEvent::GesturePinchEnd:
     case WebInputEvent::TouchCancel:
+      return false;
+    case WebInputEvent::TouchStart:
+    case WebInputEvent::TouchEnd:
+      return static_cast<const WebTouchEvent&>(event).cancelable;
+    default:
       return true;
-    case WebInputEvent::TouchStart:
-    case WebInputEvent::TouchMove:
-    case WebInputEvent::TouchEnd:
-      return !static_cast<const WebTouchEvent&>(event).cancelable;
-    default:
-      return false;
   }
 }
 
+uint32 WebInputEventTraits::GetUniqueTouchEventId(const WebInputEvent& event) {
+  if (WebInputEvent::isTouchEventType(event.type)) {
+    return static_cast<const WebTouchEvent&>(event).uniqueTouchEventId;
+  }
+  return 0U;
+}
+
 }  // namespace content