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
groupNames.add( groupName );
			}
		}
		return groupNames;
	}
	/**
	 * Determines if this element allows user properties.
	 * 
	 * @return Returns true if the element supports user-defined properties,
	 *         false if not.
	 */
	public boolean allowsUserProperties( )
	{
		return supportsUserProperties;
	}
	/**
	 * Sets the option to allow user properties.
	 * 
	 * @param flag
	 *            Whether this element supports user-defined properties.
	 */
	void setAllowsUserProperties( boolean flag )
	{
		assert !isBuilt;
		supportsUserProperties = flag;
	}
	/**
	 * Indicates whether this element is an abstract element type created as
	 * part of the element type system. Such elements are normally not visible
	 * to users -- they are used by the implementation to simplify the