Bug 179664 [Automation]CustomXML can't be set on chart[00]
Details; [Automation]CustomXML can't be set on chart[00] Step: 1.Add a chart 2.Open the properties tab and input some word in customXML Actual result: Nothing is set in customXML, when I click the enter, the customXML will come be blank.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/metadata/ElementPropertyDefn.java
* @param flag
	 *            <code>true</code> if the property value can be inherited,
	 *            <code>false</code> otherwise.
	 */
	void setCanInherit( boolean flag )
	{
		isInheritable = flag;
	}
	/**
	 * Sets the message ID for the group name.
	 * 
	 * @param id
	 *            The group name message ID.
	 */
	void setGroupNameKey( String id )
	{
		groupNameKey = id;
	}
	/**
	 * Checks whether the property is visible to the property sheet.
	 * 
	 * @return <code>true</code>.
	 */
	public boolean isVisible( )
	{
		return true;
	}
	/**
	 * Checks whether the property value is read-only in the property sheet.
	 *