Bug 163018 An error extension will lead the report contain chart can't be opened and can not new a report.
Details: An error extension will lead the report contain chart can't open In org.eclipse.birt.report.tests.model has an error extension. When run the birt use workbenck, the report contain chart can't be opened and it can not new a report.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/metadata/ElementDefn.java
* @param ns
	 *            The name space ID.
	 */
	void setNameSpaceID( int ns )
	{
		assert !isBuilt;
		nameSpaceID = ns;
		if ( nameSpaceID == MetaDataConstants.NO_NAME_SPACE )
			nameOption = MetaDataConstants.NO_NAME;
	}
	/**
	 * Sets the name option for the element. One of the following constants
	 * defined in {@link MetaDataConstants MetaDataConstants}:
	 * {@link MetaDataConstants#NO_NAME},
	 * {@link MetaDataConstants#OPTIONAL_NAME}, or
	 * {@link MetaDataConstants#REQUIRED_NAME}.
	 * 
	 * @param choice
	 *            The name option.
	 */
	void setNameOption( int choice )
	{
		nameOption = choice;
	}
	/**
	 * Sets whether the user can extend elements of this type.
	 * 
	 * @param flag
	 *            True if the element can be extended (default), or false if the
	 *            element cannot be extended.