Bug 186940 Style name in theme cannot be identify by auto when reopen the library[01]
Description: Style name in theme cannot be identify by auto when reopen the library[01] Step: 1.Open a library and add a theme 2.New a style on the theme and use the default name that is "NewStyle" 3.Save the library, close it and reopen it again. 4.New another style on the same theme Actual result: The default style name on second times is also "NewStyle" Exception result: The default style name on second times is "NewStyle1"
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/NameCommand.java
* drop if the current name is null.
	 */
	private void dropSymbol( )
	{
		if ( element.getName( ) == null || !element.isManagedByNameSpace( ) )
			return;
		int ns = ( (ElementDefn) element.getDefn( ) ).getNameSpaceID( );
		NameExecutor executor = new NameExecutor( element );
		if ( executor.getNameSpace( module ).getElement( element.getName( ) ) != element )
			return;
		getActivityStack( ).execute(
				new NameSpaceRecord( executor.getNameHelper( module ), ns,
						element, false ) );
	}
	/**
	 * Renames the namespace when call {@link #setName(String)}.
	 * 
	 * @param oldName
	 *            the old name of the element
	 */
	private void renameSymbolFrom( String oldName )
	{
		
		
		
		if ( element.isManagedByNameSpace( ) )
		{
			RenameInNameSpaceRecord record = new RenameInNameSpaceRecord(
					module, element, oldName, element.getName( ) );
			getActivityStack( ).execute( record );