Class.h (isInterface): Move implementation from natClass.cc.

* java/lang/Class.h (isInterface): Move implementation from
	natClass.cc. Declare inline.
	(Class): Add default constructor.
	* java/lang/Object.h: Update comments.
	* java/lang/natClass.cc (initializeClass): Use _Jv_InitClass to
	initialize superclass, saving a call if super is already initialized.

From-SVN: r39091

libjava/java/lang/natClass.cc

@@ -732,7 +732,7 @@ java::lang::Class::initializeClass (void)
     {
       try
 	{
-	  superclass->initializeClass ();
+	  _Jv_InitClass (superclass);
 	}
       catch (java::lang::Throwable *except)
 	{