Bug 122869 Drag a parameter from data explorer view into a table in library, a new parameter is created automatically.
Description:Drag a parameter from data explorer view into a table in library, a new parameter is created automatically. Steps to reproduce: 1. Add a cascading parameter and a table in a library file. 2. Drag a parameter from data explorer view into a table cell in layout editor. 3. Find that a new parameter was added in data explorer view automatically.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ExpressionBuilder.java
{
	private static final String DIALOG_TITLE = Messages
			.getString( "ExpressionBuidler.Dialog.Title" ); 
	private static final String PROMRT_MESSAGE = Messages
			.getString( "ExpressionBuilder.Message.Prompt" ); 
	private static final String LABEL_FUNCTIONS = Messages
			.getString( "ExpressionBuilder.Label.Functions" ); 
	private static final String LABEL_SUB_CATEGORY = Messages
			.getString( "ExpressionBuilder.Label.SubCategory" ); 
	private static final String LABEL_CATEGORY = Messages
			.getString( "ExpressionBuilder.Label.Category" ); 
	private static final String LABEL_OPERATORS = Messages
			.getString( "ExpressionBuilder.Label.Operators" ); 
	private static final String TOOL_TIP_TEXT_REDO = Messages
			.getString( "TextEditDialog.toolTipText.redo" ); 
	private static final String TOOL_TIP_TEXT_UNDO = Messages
			.getString( "TextEditDialog.toolTipText.undo" ); 
	private static final String TOOL_TIP_TEXT_DELETE = Messages
			.getString( "TextEditDialog.toolTipText.delete" ); 
	private static final String TOOL_TIP_TEXT_PASTE = Messages
			.getString( "TextEditDialog.toolTipText.paste" ); 
	private static final String TOOL_TIP_TEXT_CUT = Messages
			.getString( "TextEditDialog.toolTipText.cut" ); 
	private static final String TOOL_TIP_TEXT_COPY = Messages
			.getString( "TextEditDialog.toolTipText.copy" ); 
	private class TableContentProvider implements IStructuredContentProvider