gestures: Generate only either scroll-end or fling-start events at the end of a scroll gesture.

content/browser/renderer_host/render_widget_host_view_win.cc

 // 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_win.h"
 
 #include <algorithm>
 #include <map>
 #include <peninputpanel_i.c>
 #include <stack>
@@ skipping 2862 matching lines @@
     ::DestroyWindow(tooltip_hwnd_);
   tooltip_hwnd_ = NULL;
 }
 
 bool RenderWidgetHostViewWin::ForwardGestureEventToRenderer(
     ui::GestureEvent* gesture) {
   if (!render_widget_host_)
     return false;
 
   LocalGestureEvent* local = static_cast<LocalGestureEvent*>(gesture);
-  if (local->data().type == WebKit::WebGestureEvent::Undefined)
+  if (local->data().type == WebKit::WebInputEvent::Undefined)
     return false;
-  const WebKit::WebGestureEvent& generatedEvent = local->data();
-  render_widget_host_->ForwardGestureEvent(generatedEvent);
+  const WebKit::WebGestureEvent& gesture_event = local->data();
+  if (gesture_event.type == WebKit::WebInputEvent::GestureFlingStart) {
+    // WebKit requires that a scroll ends first before a fling starts.

[rjkroege, 2012/08/09 16:51:06]

same comment. :-)

+    WebKit::WebGestureEvent scroll_end = gesture_event;
+    scroll_end.type = WebKit::WebInputEvent::GestureScrollEnd;
+    render_widget_host_->ForwardGestureEvent(scroll_end);
+  }
+  render_widget_host_->ForwardGestureEvent(gesture_event);
   return true;
 }
 
 void RenderWidgetHostViewWin::ForwardMouseEventToRenderer(UINT message,
                                                           WPARAM wparam,
                                                           LPARAM lparam) {
   TRACE_EVENT0("browser",
                "RenderWidgetHostViewWin::ForwardMouseEventToRenderer");
   if (!render_widget_host_) {
     TRACE_EVENT0("browser", "EarlyOut_NoRWH");
@@ skipping 269 matching lines @@
   // receive a focus change in the context of a pointer down message, it means
   // that the pointer down message occurred on the edit field and we should
   // display the on screen keyboard
   if (!received_focus_change_after_pointer_down_ && virtual_keyboard_)
     DisplayOnScreenKeyboardIfNeeded();
   received_focus_change_after_pointer_down_ = false;
   pointer_down_context_ = false;
 }
 
 }  // namespace content