1 files changed, 32 insertions, 24 deletions

diff --git a/Source/WebCore/page/scrolling/ScrollingStateTree.h b/Source/WebCore/page/scrolling/ScrollingStateTree.h
index 59659e534..3b256151a 100644
--- a/Source/WebCore/page/scrolling/ScrollingStateTree.h
+++ b/Source/WebCore/page/scrolling/ScrollingStateTree.h
@@ -23,14 +23,11 @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef ScrollingStateTree_h
-#define ScrollingStateTree_h
+#pragma once
 
 #if ENABLE(ASYNC_SCROLLING) || USE(COORDINATED_GRAPHICS)
 
-#include "ScrollingStateScrollingNode.h"
-#include <wtf/OwnPtr.h>
-#include <wtf/PassOwnPtr.h>
+#include "ScrollingStateFrameScrollingNode.h"
 #include <wtf/RefPtr.h>
  
 namespace WebCore {
@@ -43,29 +40,30 @@ class AsyncScrollingCoordinator;
 // the scrolling thread, avoiding locking. 
 
 class ScrollingStateTree {
+    WTF_MAKE_FAST_ALLOCATED;
     friend class ScrollingStateNode;
 public:
-    
-    static PassOwnPtr<ScrollingStateTree> create(AsyncScrollingCoordinator* = 0);
-    ~ScrollingStateTree();
+    WEBCORE_EXPORT ScrollingStateTree(AsyncScrollingCoordinator* = nullptr);
+    WEBCORE_EXPORT ~ScrollingStateTree();
 
-    ScrollingStateScrollingNode* rootStateNode() const { return m_rootStateNode.get(); }
-    ScrollingStateNode* stateNodeForID(ScrollingNodeID);
+    ScrollingStateFrameScrollingNode* rootStateNode() const { return m_rootStateNode.get(); }
+    WEBCORE_EXPORT ScrollingStateNode* stateNodeForID(ScrollingNodeID) const;
 
-    ScrollingNodeID attachNode(ScrollingNodeType, ScrollingNodeID, ScrollingNodeID parentID);
+    WEBCORE_EXPORT ScrollingNodeID attachNode(ScrollingNodeType, ScrollingNodeID, ScrollingNodeID parentID);
     void detachNode(ScrollingNodeID);
     void clear();
     
-    const Vector<ScrollingNodeID>& removedNodes() const { return m_nodesRemovedSinceLastCommit; }
-    void setRemovedNodes(Vector<ScrollingNodeID>);
+    const HashSet<ScrollingNodeID>& removedNodes() const { return m_nodesRemovedSinceLastCommit; }
+    WEBCORE_EXPORT void setRemovedNodes(HashSet<ScrollingNodeID>);
 
     // Copies the current tree state and clears the changed properties mask in the original.
-    PassOwnPtr<ScrollingStateTree> commit(LayerRepresentation::Type preferredLayerRepresentation);
+    WEBCORE_EXPORT std::unique_ptr<ScrollingStateTree> commit(LayerRepresentation::Type preferredLayerRepresentation);
 
-    void setHasChangedProperties(bool = true);
+    WEBCORE_EXPORT void setHasChangedProperties(bool = true);
     bool hasChangedProperties() const { return m_hasChangedProperties; }
 
     bool hasNewRootStateNode() const { return m_hasNewRootStateNode; }
+    void setHasNewRootStateNode(bool hasNewRoot) { m_hasNewRootStateNode = hasNewRoot; }
     
     int nodeCount() const { return m_stateNodeMap.size(); }
 
@@ -76,17 +74,24 @@ public:
     void setPreferredLayerRepresentation(LayerRepresentation::Type representation) { m_preferredLayerRepresentation = representation; }
 
 private:
-    ScrollingStateTree(AsyncScrollingCoordinator*);
-
-    void setRootStateNode(PassOwnPtr<ScrollingStateScrollingNode> rootStateNode) { m_rootStateNode = rootStateNode; }
+    void setRootStateNode(Ref<ScrollingStateFrameScrollingNode>&& rootStateNode) { m_rootStateNode = WTFMove(rootStateNode); }
     void addNode(ScrollingStateNode*);
-    void removeNode(ScrollingStateNode*);
-    void didRemoveNode(ScrollingNodeID);
+
+    Ref<ScrollingStateNode> createNode(ScrollingNodeType, ScrollingNodeID);
+
+    bool nodeTypeAndParentMatch(ScrollingStateNode&, ScrollingNodeType, ScrollingNodeID parentID) const;
+
+    enum class SubframeNodeRemoval { Delete, Orphan };
+    void removeNodeAndAllDescendants(ScrollingStateNode*, SubframeNodeRemoval = SubframeNodeRemoval::Delete);
+
+    void recursiveNodeWillBeRemoved(ScrollingStateNode* currNode, SubframeNodeRemoval);
+    void willRemoveNode(ScrollingStateNode*);
 
     AsyncScrollingCoordinator* m_scrollingCoordinator;
     StateNodeMap m_stateNodeMap;
-    OwnPtr<ScrollingStateScrollingNode> m_rootStateNode;
-    Vector<ScrollingNodeID> m_nodesRemovedSinceLastCommit;
+    RefPtr<ScrollingStateFrameScrollingNode> m_rootStateNode;
+    HashSet<ScrollingNodeID> m_nodesRemovedSinceLastCommit;
+    HashMap<ScrollingNodeID, RefPtr<ScrollingStateNode>> m_orphanedSubframeNodes;
     bool m_hasChangedProperties;
     bool m_hasNewRootStateNode;
     LayerRepresentation::Type m_preferredLayerRepresentation;
@@ -94,6 +99,9 @@ private:
 
 } // namespace WebCore
 
-#endif // ENABLE(ASYNC_SCROLLING) || USE(COORDINATED_GRAPHICS)
+#ifndef NDEBUG
+void showScrollingStateTree(const WebCore::ScrollingStateTree*);
+void showScrollingStateTree(const WebCore::ScrollingStateNode*);
+#endif
 
-#endif // ScrollingStateTree_h
+#endif // ENABLE(ASYNC_SCROLLING) || USE(COORDINATED_GRAPHICS)