AttributeMenuTool: added option to always show prompt in combo box.
Fixed backwards compatibility with old default panelTitle.

Change-Id: I8a200801929c22b153c8b6fb1618f4e1bc0f629c
Preventing DraggablePanel from causing ComboBox to crash on mouseDown.
Preventing createChildren() from creating duplicate children in classes
that extend DraggablePanel.
Fixed DraggablePanel moveIcon display bug on popup windows.
ErrorLogPanel menu item "Show all menus and controls" now enables
borders and titlebar buttons for DraggablePanels.

Change-Id: I03c35d686507e6faafcbac9d3ebb27b96ced8680