Fixes bug libgcj/8170

Fixes bug libgcj/8170
       * java/lang/ClassLoader.java (loadClass): Don't rewrap
       ClassNotFoundException.
       * gnu/java/lang/MainThread.java (run): Chain NoClassDefFoundError.
       * gnu/gcj/runtime/NameFinder.java (remove_interpreter): Removed.
       (remove_internal): New field superceding remove_interpreter.
       (sanitizeStack): Remove all no-package classes starting with "_Jv_".
       Remove no-class methods starting with "_Jv_". And Replace null
       class or method names with the empty string. Stop at either the
       MainThread or a real Thread run() method.
       (newElement): Made static.
       * java/net/URLClassLoader.java (findClass): Throw
       ClassNotFoundExceptions including urls, plus parent using toString().
       (thisString): New field.
       (toString): New method.

From-SVN: r94935

libjava/java/lang/ClassLoader.java

@@ -288,8 +288,6 @@ public abstract class ClassLoader
     if (c != null)
       return c;
 
-    ClassNotFoundException ex = null;
-
     // Can the class be loaded by a parent?
     try
       {
@@ -306,20 +304,9 @@ public abstract class ClassLoader
       }
     catch (ClassNotFoundException e)
       {
-	ex = e;
       }
     // Still not found, we have to do it ourself.
-    try
-      {
-	c = findClass(name);
-      }
-    catch (ClassNotFoundException cause)
-      {
-	if (ex != null)
-	  throw new ClassNotFoundException(ex.toString(), cause);
-	else
-	  throw cause;
-      }
+    c = findClass(name);
     if (resolve)
       resolveClass(c);
     return c;