Compute snap offsets (both repeat and element based)

Source/core/dom/ContainerNode.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2013 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 33 matching lines @@
 #include "core/html/HTMLCollection.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/html/HTMLTagCollection.h"
 #include "core/html/RadioNodeList.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/layout/LayoutInline.h"
 #include "core/layout/LayoutText.h"
 #include "core/layout/LayoutTheme.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/line/InlineTextBox.h"
+#include "core/page/scrolling/SnapCoordinator.h"
 #include "platform/EventDispatchForbiddenScope.h"
 #include "platform/ScriptForbiddenScope.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 static void dispatchChildInsertionEvents(Node&);
 static void dispatchChildRemovalEvents(Node&);
 
@@ skipping 801 matching lines @@
         for (ShadowRoot* shadowRoot = node.youngestShadowRoot(); shadowRoot; shadowRoot = shadowRoot->olderShadowRoot())
             notifyNodeRemoved(*shadowRoot);
     }
 }
 
 void ContainerNode::attach(const AttachContext& context)
 {
     attachChildren(context);
     clearChildNeedsStyleRecalc();
     Node::attach(context);
+
+    if (document().frame() && document().frame()->snapCoordinator())

[esprehn, 2015/09/24 17:37:41]

ditto checking for frame() doesn't make sense, this is also not the right layer
for this. This should be in Element, not ContainerNode.

[majidvp, 2015/10/15 21:47:02]

Done.

+        document().frame()->snapCoordinator()->attach(*this);
 }
 
 void ContainerNode::detach(const AttachContext& context)
 {
     detachChildren(context);
     setChildNeedsStyleRecalc();
+    if (document().frame() && document().frame()->snapCoordinator())
+        document().frame()->snapCoordinator()->detach(*this);

[esprehn, 2015/09/24 17:37:41]

frame() checks here don't make sense, we must have a frame if we're inside
detach. I also don't like the generic "detach" callbacks out to code like this.
This code should read like:

if (isSnapContainer())
  document().frameView()->removeSnapContainer(*this);
if (isSnapElement())
  document().frameView()->removeSnapElement(*this);

this code should also be in Element, not ContainerNode.

[majidvp, 2015/10/15 21:47:02]

Done.

+
     Node::detach(context);
 }
 
 void ContainerNode::childrenChanged(const ChildrenChange& change)
 {
     document().incDOMTreeVersion();
     if (!change.byParser && change.type != TextChanged)
         document().updateRangesAfterChildrenChanged(this);
     invalidateNodeListCachesInAncestors();
     if (change.isChildInsertion() && !childNeedsStyleRecalc()) {
@@ skipping 635 matching lines @@
         return true;
 
     if (node->isElementNode() && toElement(node)->shadow())
         return true;
 
     return false;
 }
 #endif
 
 } // namespace blink