Bug 113938 Report is marked dirty when open/close cascading parameter dialog without doing any operation on it
description: Report is marked dirty when open/close cascading parameter dialog without doing any operation on it steps to reproduce: 1.new a cascading parameter group 2.save the reprot 3.double click the cascading parameter to bring out edit box 4.click OK to close edit box actual result: Report has been marked dirty expected result: No dirty marked for that no operations done in edit parameter dialog
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ExpressionProvider.java
"-", 
			"*", 
			"/", 
			OPERATOR_SEPARATOR, "!", 
			"=", 
			"<", 
			">", 
			OPERATOR_SEPARATOR, "&", 
			"|", 
			"(", 
			")" 
	};
	
	private static final Operator[] OPERATORS_ASSIGNMENT = new Operator[]{
			new Operator( "=", "ExpressionProvider.Operator.Assign" ), 
			new Operator( "+=", "ExpressionProvider.Operator.AddTo" ), 
			new Operator( "-=", "ExpressionProvider.Operator.SubFrom" ), 
			new Operator( "*=", "ExpressionProvider.Operator.MultTo" ), 
			new Operator( "/=", "ExpressionProvider.Operator.DividingFrom" ), 
	};
	
	private static Operator[] OPERATORS_COMPARISON = new Operator[]{
			new Operator( "==", "ExpressionProvider.Operator.Equals" ), 
			new Operator( "<", "ExpressionProvider.Operator.Less" ), 
			new Operator( "<=", "ExpressionProvider.Operator.LessEqual" ),  
			new Operator( "!=", "ExpressionProvider.Operator.NotEqual" ),  
			new Operator( ">", "ExpressionProvider.Operator.Greater" ), 
			new Operator( ">=", "ExpressionProvider.Operator.GreaterEquals" ), 
	};