re PR libgcj/24321 (instanceof erroneously causes class initialization)

PR java/24321:
	* testsuite/libjava.lang/pr24321.java: New file.
	* testsuite/libjava.lang/pr24321.out: New file.
	* java/lang/natClass.cc (isInstance): Don't initialize class.
	(isAssignableFrom): Likewise.

From-SVN: r111603

libjava/testsuite/libjava.lang/pr24321.java

@@ -0,0 +1,21 @@
+public class pr24321 {
+  static class Z {
+    static {
+      System.out.println("init");
+    }
+  }
+
+  static class Y extends Z { }
+
+  public static Object x () { return new Object(); }
+
+  public static void main(String[] args) throws Throwable
+  {
+    System.out.println(x() instanceof Z);
+
+    ClassLoader cl = pr24321.class.getClassLoader();
+    Class zk = Class.forName("pr24321$Z", false, cl);
+    Class yk = Class.forName("pr24321$Y", false, cl);
+    System.out.println(zk.isAssignableFrom(yk));
+  }
+}

libjava/testsuite/libjava.lang/pr24321.out

@@ -0,0 +1,2 @@
+false
+true