Check for abstract method in javadoc does not conform to the language model

The isAbstract() method, in com.sun.tools.MethodDocImpl.java that checks if a method is abstract or not, does not conform to the language model. isAbstract() checks whether the abstract modifier needs to be printed in the generated javadoc. This method returns false for interface methods eventhough these methods are abstract.

The isAbstract() method needs to return true if the method is abstract and the doclet need to have a methods which decides printing the abstract modifier.