7039089: G1: changeset for 7037276 broke heap verification, and related cleanups Summary: In G1 heap verification, we no longer scan perm to G1-collected heap refs as part of process_strong_roots() but rather in a separate explicit oop iteration over the perm gen. This preserves the original perm card-marks. Added a new assertion in younger_refs_iterate() to catch a simple subcase where the user may have forgotten a prior save_marks() call, as happened in the case of G1's attempt to iterate perm to G1 refs when verifying the heap before exit. The assert was deliberately weakened for ParNew+CMS and will be fixed for that combination in a future CR. Also made some (non-G1) cleanups related to code and comments obsoleted by the migration of Symbols to the native heap. Reviewed-by: iveresov, jmasa, tonyp

// A simple class to extend an abstract class and get loaded with different
// loaders.  This class is loaded via LOADER2.  A similar named class will
// be loaded via LOADER1.
public class many_loader extends bug_21227 {
  final Object _ref_to_be_p0wned;

  many_loader() {
    _ref_to_be_p0wned = bug_21227._p0wnee;
    System.out.println("Gonna hack this thing: " + _ref_to_be_p0wned.toString() );
  }

  // I need to compile (hence call in a loop) a function which returns a value
  // loaded from classloader other than the system one.  The point of this
  // call is to give me an abstract 'hook' into a function loaded with a
  // foreign loader.
  public many_loader[] make( IFace iface ) { 
    throw new Error("do not call me");
  }
}