StackWalker.getCallerClass() can return false results if running with -XX:+ShowHiddenFrames

The following small test program will a false result for `StackWalker.getCallerClass()` if running with `-XX:+ShowHiddenFrames` (i.e. `class InjectedInvoker/0x0000000800062440` instead of `class GetCallerClass`):

```
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.reflect.Method;
import java.util.Set;

public class GetCallerClass {
    private static Method gcc;

    static {
        try {
            gcc = GetCallerClass.class.getDeclaredMethod("getCallerClass");
        } catch (Exception ex) {
            System.out.println(ex);
        }
    }

    private static final StackWalker WALKER = StackWalker.getInstance(Set.of(StackWalker.Option.RETAIN_CLASS_REFERENCE), 3);
    public static void getCallerClass() {
        System.out.println(WALKER.getCallerClass());
    }

    public static void main(String[] args) throws Throwable {
        MethodType mt = MethodType.methodType(Object.class, Object.class, Object[].class);
        MethodHandle mh =
            MethodHandles.
            lookup().
            findVirtual(Method.class, "invoke", mt).
            bindTo(gcc);
        mh.invoke(null, null);
    }
}
```