Bug 119331 Library - name space terminology and behavior
During BIRT 2.0 library feature review meeting the following change was decided. - Change the term namespace to 'prefix' - By default use the library name as the prefix ( namespace ); the dialog to input prefix should be prompted only if hte auto generated prefix is not unique.
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DNDUtil.java
return CONTAIN_NO;
		}
		for ( int i = 0; i < childHandles.length; i++ )
		{
			if ( !( childHandles[i] instanceof DesignElementHandle )
					|| handleValidateTargetCanContainByContainer( targetObj,
							(DesignElementHandle) childHandles[i],
							validateContainer ) == CONTAIN_NO )
			{
				return CONTAIN_NO;
			}
		}
		return CONTAIN_THIS;
	}
	protected static int handleValidateTargetCanContainElementHandle(
			DesignElementHandle targetHandle, DesignElementHandle childHandle,
			boolean validateContainer )
	{
		if ( targetHandle instanceof CascadingParameterGroupHandle )
		{
			return childHandle.getContainer( ) == targetHandle ? CONTAIN_THIS
					: CONTAIN_NO;
		}
		else if ( targetHandle.canContain( DEUtil.getDefaultSlotID( targetHandle ),
				childHandle ) )
		{
			return CONTAIN_THIS;
		}
		else if ( targetHandle instanceof ParameterGroupHandle
				&& childHandle instanceof ParameterGroupHandle )