Bug 140542 label can't be displayed without resource file or unmatched key
Steps to reproduce: 1.New a report, add a lable with text "aaa" 2.Add a resource file for the report, set key to "key1", value to "actuate", apply the value to the label 3.Clear the resource file in Property Editor->General->Resource File (or change the key to "abc") 4.Preview the report Expected result: 1.Display label text "aaa" on preview or 2.Give a warning message to say resource file is not found or unmatched key Actual result: Nothing displays on preview
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
* 
	 * @param name
	 *            the master page name.
	 * @return the master page, if found, otherwise null.
	 */
	public DesignElement findPage( String name )
	{
		return resolveNativeElement( name, PAGE_NAME_SPACE );
	}
	/**
	 * Finds a parameter by name in this module and the included modules.
	 * 
	 * @param name
	 *            The parameter name.
	 * @return The parameter, if found, otherwise null.
	 */
	public DesignElement findParameter( String name )
	{
		return resolveNativeElement( name, PARAMETER_NAME_SPACE );
	}
	/**
	 * Gets a name space.
	 * 
	 * @param ns
	 *            The name space ID.
	 * @return The name space.
	 */
	public NameSpace getNameSpace( int ns )
	{
		assert ns >= 0 && ns < NAME_SPACE_COUNT;