Bubble scroll events from WebView guest to embedder.

content/browser/frame_host/render_widget_host_view_guest.cc

 // Copyright 2014 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 "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_factory.h"
@@ skipping 645 matching lines @@
     return;
   }
 
   if (blink::WebInputEvent::isGestureEventType(event->type)) {
     host_->ForwardGestureEvent(
         *static_cast<const blink::WebGestureEvent*>(event));
     return;
   }
 }
 
+namespace {
+
+bool IsScrollEvent(const blink::WebInputEvent& event) {
+  return event.type == blink::WebInputEvent::GestureScrollBegin ||
+         event.type == blink::WebInputEvent::GestureScrollUpdate ||
+         event.type == blink::WebInputEvent::GestureScrollEnd ||
+         event.type == blink::WebInputEvent::MouseWheel;
+}
+
+}  // namespace
+
+void RenderWidgetHostViewGuest::GestureEventAck(
+    const blink::WebGestureEvent& event,
+    InputEventAckState ack_result) {
+  if (IsScrollEvent(event))
+    guest_->SendScrollCompletion(ack_result == INPUT_EVENT_ACK_STATE_CONSUMED);
+}
+
+void RenderWidgetHostViewGuest::WheelEventAck(
+    const blink::WebMouseWheelEvent& event,
+    InputEventAckState ack_result) {
+  if (IsScrollEvent(event))
+    guest_->SendScrollCompletion(ack_result == INPUT_EVENT_ACK_STATE_CONSUMED);
+}
+
 }  // namespace content