corrected wxTreeCtrl::GetBestSize() for a control with borders

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@43640 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/treebase.cpp

@@ -163,7 +163,12 @@ wxSize wxTreeCtrlBase::DoGetBestSize() const
     if ( !size.x || !size.y )
         size = wxControl::DoGetBestSize();
     else
+    {
+        // Add border size
+        size += GetWindowBorderSize();
+
         CacheBestSize(size);
+    }
 
     return size;
 }