stddoclet: Summary heading missing when class has inherited but no implemt'd API

Summary headings on class/interface pages are missing for members
that have only inherited members (and no implement members).
These summary headings should appear.

For example, the Container class does not implement any fields,
but inherits fields from Component. There should be a heading
"Field Summary" ahead of the table "Fields inherited from class java.awt.Component".
In JDK 1.2 Beta4, see:

http://java.sun.com/products/jdk/1.2/docs/api/java.awt.Container.html

In other examples, the same would be true for methods, constructors and
inner classes.