Rename Document::ownerElement to localOwner and fix main frame checks.

third_party/WebKit/Source/core/input/EventHandler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 66 matching lines @@
 #include "core/page/AutoscrollController.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/DragController.h"
 #include "core/page/DragState.h"
 #include "core/page/FocusController.h"
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/page/SpatialNavigation.h"
 #include "core/page/TouchAdjustment.h"
 #include "core/page/scrolling/OverscrollController.h"
+#include "core/page/scrolling/RootScroller.h"
 #include "core/page/scrolling/ScrollState.h"
 #include "core/paint/PaintLayer.h"
 #include "core/style/ComputedStyle.h"
 #include "core/svg/SVGDocumentExtensions.h"
 #include "platform/PlatformGestureEvent.h"
 #include "platform/PlatformKeyboardEvent.h"
 #include "platform/PlatformTouchEvent.h"
 #include "platform/PlatformWheelEvent.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/TraceEvent.h"
@@ skipping 2325 matching lines @@
         if (m_frame->isMainFrame())
             m_frame->host()->topControls().scrollBegin();
     }
     return WebInputEventResult::HandledSystem;
 }
 
 bool EventHandler::isRootScroller(const Node& node) const
 {
     // The root scroller is the one Element on the page designated to perform
     // "viewport actions" like top controls movement and overscroll glow.
-
-    if (!node.isElementNode() || node.document().ownerElement())
+    if (!node.isElementNode() || !frameHost() || !frameHost()->rootScroller())
         return false;
 
-    return node.document().rootScroller() == toElement(&node);
+    return frameHost()->rootScroller()->get() == toElement(&node);

[esprehn, 2016/05/09 21:22:34]

you don't need to cast a node to an Element to compare it. Also this whole
function is:

if (!frameHost())
  return false;
return frameHost()->rootScroller() == node;

[bokan, 2016/05/09 22:26:18]

Done, but this will break silently if Element or ContainerNode ever multiply
inherit from an additional class before Node. Do we disallow MI with data
members?
The rootScroller check is needed since it can be null in the OOPIF case right
now. 

 }
 
 WebInputEventResult EventHandler::handleGestureScrollUpdate(const PlatformGestureEvent& gestureEvent)
 {
     ASSERT(gestureEvent.type() == PlatformEvent::GestureScrollUpdate);
 
     // Negate the deltas since the gesture event stores finger movement and
     // scrolling occurs in the direction opposite the finger's movement
     // direction. e.g. Finger moving up has negative event delta but causes the
     // page to scroll down causing positive scroll delta.
@@ skipping 1254 matching lines @@
 {
 #if OS(MACOSX)
     return static_cast<PlatformEvent::Modifiers>(PlatformEvent::CtrlKey | PlatformEvent::AltKey);
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 FrameHost* EventHandler::frameHost()
 {
+    return const_cast<FrameHost*>(
+        static_cast<const EventHandler&>(*this).frameHost());

[esprehn, 2016/05/09 21:22:34]

woah, just mark the getter as const

[bokan, 2016/05/09 22:26:18]

Done.

+}
+
+const FrameHost* EventHandler::frameHost() const

[esprehn, 2016/05/09 21:22:34]

no need for this, the getter can just be const

[dcheng, 2016/05/09 21:26:16]

I think we should just make this FrameHost* EventHandler::frameHost() const, for
consistency with the rest of Blink (e.g. the ownerElement method renamed in this
CL is a const-method returning a non-const pointer still).

I think it's unlikely we're going to want this pattern in Blink, unless someone
can figure out what this would look like and what the benefits would be.

[bokan, 2016/05/09 22:26:18]

Done.

+{
     if (!m_frame->page())
         return nullptr;
 
     return &m_frame->page()->frameHost();
 }
 
 } // namespace blink