Ensure that trackpad and trackpoint scrolling works on Windows desktop Aura with legacy trackpad dr…

content/browser/renderer_host/render_widget_host_view_aura.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_aura.h"
 
 #include "base/auto_reset.h"
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback_helpers.h"
@@ skipping 2855 matching lines @@
   if (!IsXButtonUpEvent(event))
     event->SetHandled();
 }
 
 void RenderWidgetHostViewAura::OnScrollEvent(ui::ScrollEvent* event) {
   TRACE_EVENT0("input", "RenderWidgetHostViewAura::OnScrollEvent");
   if (touch_editing_client_ && touch_editing_client_->HandleInputEvent(event))
     return;
 
   if (event->type() == ui::ET_SCROLL) {
+#if !defined(OS_WIN)

[sky, 2014/01/10 16:43:21]

Should this be an in metro mode check?

[ananta, 2014/01/10 18:59:21]

Not sure about that. From inspection it appears that this handler assumes that
scroll events come in via a gesture which may not be true
always for Windows. Added a TODO to look into this.

     if (event->finger_count() != 2)
       return;
+#endif
     blink::WebGestureEvent gesture_event =
         MakeWebGestureEventFlingCancel();
     host_->ForwardGestureEvent(gesture_event);
     blink::WebMouseWheelEvent mouse_wheel_event =
         MakeWebMouseWheelEvent(event);
     host_->ForwardWheelEvent(mouse_wheel_event);
     RecordAction(UserMetricsAction("TrackpadScroll"));
   } else if (event->type() == ui::ET_SCROLL_FLING_START ||
              event->type() == ui::ET_SCROLL_FLING_CANCEL) {
     blink::WebGestureEvent gesture_event =
@@ skipping 613 matching lines @@
     RenderWidgetHost* widget) {
   return new RenderWidgetHostViewAura(widget);
 }
 
 // static
 void RenderWidgetHostViewPort::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content