Bug 196257 NPE when call ArgumentInfoList.argumentsIterator()
When call ArgumentInfoList.argumentsIterator(), it will throw NPE sometimes. This is caused the inner "arguments" member may not initialized when call this method.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/scripts/MethodInfo.java
return false;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.api.metadata.IMethodInfo#isStatic()
	 */
	public boolean isStatic( )
	{
		return Modifier.isStatic( method.getModifiers( ) );
	}
	public IClassInfo getClassReturnType( )
	{
		return new ClassInfo( method.getReturnType( ) );
	}
	/**
	 * Adds an optional argument list to the method information.
	 * 
	 * @param argumentList
	 *            an optional argument list
	 * 
	 */
	void addArgumentList( Class[] argumentList )
	{
		if ( arguments == null )
			arguments = new ArrayList( );
		ArgumentInfoList argumentInfoList = new ArgumentInfoList( argumentList );
		arguments.add( argumentInfoList );
	}
}