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 testCommand( ) throws Exception
	{
		openDesign( FILE_NAME );
		assertNotNull( designHandle );
		
		TabularCubeHandle cube = (TabularCubeHandle) designHandle
				.findCube( "testCube" ); 
		try
		{
			cube.setName( null );
			fail( );
		}
		catch ( NameException e )
		{
		}
		IDesignElement clonedCube = cube.copy( );
		assertNotNull( clonedCube );
		designHandle.rename( clonedCube.getHandle( design ) );
		designHandle.getSlot( IReportDesignModel.CUBE_SLOT ).add(
				clonedCube.getHandle( design ) );
		
		save( );
		assertTrue( compareFile( "CubeParserTest_golden_1.xml" ) ); 		
	}
	/**
	 * Tests cases for cube1 extends another cube2.
	 * 
	 * <ul>
	 * <li>if one new access control is added to the cube1. Access controls on
	 * cube2 will be copies to cube1 first.