Forward GestureFlingStart in OOPIF, re-enable DCHECK.

content/browser/frame_host/cross_process_frame_connector.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 "content/browser/frame_host/cross_process_frame_connector.h"
 
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_hittest.h"
 #include "cc/surfaces/surface_manager.h"
 #include "content/browser/compositor/surface_utils.h"
@@ skipping 165 matching lines @@
     const TouchEventWithLatencyInfo& touch,
     InputEventAckState ack_result) {
   auto* main_view = GetRootRenderWidgetHostView();
   if (main_view)
     main_view->ProcessAckedTouchEvent(touch, ack_result);
 }
 
 void CrossProcessFrameConnector::BubbleScrollEvent(
     const blink::WebGestureEvent& event) {
   DCHECK(event.GetType() == blink::WebInputEvent::kGestureScrollUpdate ||
-         event.GetType() == blink::WebInputEvent::kGestureScrollEnd);
+         event.GetType() == blink::WebInputEvent::kGestureScrollEnd ||
+         event.GetType() == blink::WebInputEvent::kGestureFlingStart);
   auto* parent_view = GetParentRenderWidgetHostView();
 
   if (!parent_view)
     return;
 
   auto* event_router =
       RenderWidgetHostImpl::From(parent_view->GetRenderWidgetHost())
           ->delegate()
           ->GetInputEventRouter();
 
   gfx::Vector2d offset_from_parent = child_frame_rect_.OffsetFromOrigin();
   blink::WebGestureEvent resent_gesture_event(event);
   // TODO(kenrb, wjmaclean): Do we need to account for transforms here?
   // See https://crbug.com/626020.
   resent_gesture_event.x += offset_from_parent.x();
   resent_gesture_event.y += offset_from_parent.y();
   if (event.GetType() == blink::WebInputEvent::kGestureScrollUpdate) {
     event_router->BubbleScrollEvent(parent_view, resent_gesture_event);
     is_scroll_bubbling_ = true;
-  } else if (event.GetType() == blink::WebInputEvent::kGestureScrollEnd &&
+  } else if ((event.GetType() == blink::WebInputEvent::kGestureScrollEnd ||
+              event.GetType() == blink::WebInputEvent::kGestureFlingStart) &&
              is_scroll_bubbling_) {
     event_router->BubbleScrollEvent(parent_view, resent_gesture_event);
     is_scroll_bubbling_ = false;
   }
 }
 
 bool CrossProcessFrameConnector::HasFocus() {
   RenderWidgetHostViewBase* root_view = GetRootRenderWidgetHostView();
   if (root_view)
     return root_view->HasFocus();
@@ skipping 112 matching lines @@
 
   if (parent) {
     return static_cast<RenderWidgetHostViewBase*>(
         parent->current_frame_host()->GetView());
   }
 
   return nullptr;
 }
 
 }  // namespace content