1. changed spelling error in wxTR_HAS_VARIABLE_HEIGHT (missing 'E')

2. compile fix for dcscreen.cpp
3. editing labels in place works in the tree ctrl and shown in the sample
4. sped up items deletion in the listview


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@3110 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/treectrl/treetest.h

@@ -71,6 +71,13 @@ public:
 protected:
     virtual int OnCompareItems(const wxTreeItemId& i1, const wxTreeItemId& i2);
 
+    // is this the test item which we use in several event handlers?
+    bool IsTestItem(const wxTreeItemId& item)
+    {
+        // the test item is the first child folder
+        return GetParent(item) == GetRootItem() && !GetPrevSibling(item);
+    }
+
 private:
     void AddItemsRecursively(const wxTreeItemId& idParent,
                              size_t nChildren,