Bug 188578 Add "displayColumnName" on TabularLevel
Add Property "displayColumnName" on TabbularLevel and corresponding APIs on handle. Property Type: expression.
model/org.eclipse.birt.report.model.tests/test/org/eclipse/birt/report/model/parser/TabularCubeParserTest.java
*/
	public void testContentElementCommandOnCube( ) throws Exception
	{
		openDesign( FILE_NAME_EXTENDS );
		
		TabularCubeHandle cube = (TabularCubeHandle) designHandle
				.findCube( "testCube1" ); 
		
		Iterator cubeAccess = cube.accessControlsIterator( );
		AccessControlHandle tmpAccess = (AccessControlHandle) cubeAccess.next( );
		tmpAccess.setPermission( DesignChoiceConstants.ACCESS_PERMISSION_ALLOW );
		save( );
		assertTrue( compareFile( "TabularCubeAccessControl_golden_1.xml" ) ); 
		designHandle.getCommandStack( ).undo( );
		save( );
		assertTrue( compareFile( "TabularCubeAccessControl_golden_2.xml" ) ); 
		tmpAccess.addRole( "new 2nd role" ); 
		save( );
		assertTrue( compareFile( "TabularCubeAccessControl_golden_3.xml" ) ); 
		designHandle.getCommandStack( ).undo( );
		tmpAccess.removeRole( "cube role1" ); 
		save( );
		assertTrue( compareFile( "TabularCubeAccessControl_golden_4.xml" ) ); 
		designHandle.getCommandStack( ).undo( );
		tmpAccess.removeRole( "cube role1" ); 
		tmpAccess.setPermission( DesignChoiceConstants.ACCESS_PERMISSION_ALLOW );
		save( );
		assertTrue( compareFile( "TabularCubeAccessControl_golden_5.xml" ) ); 
	}
	/**