Move getThreads() to native code for reusing on other place. This is also more like the Java behavior.

openjdk/java/lang/Thread.java

@@ -2047,20 +2047,7 @@ class Thread implements Runnable {
     
     private static native StackTraceElement[] getStackTrace(cli.System.Diagnostics.StackTrace stack);
 
-    private static Thread[] getThreads() {
-        return (Thread[])AccessController.doPrivileged(
-            new PrivilegedAction() {
-                public Object run() {
-                    ThreadGroup root = getMainThreadGroup();
-                    for (; ; ) {
-                        Thread[] threads = new Thread[root.activeCount()];
-                        if (root.enumerate(threads) == threads.length) {
-                            return threads;
-                        }
-                    }
-                }
-            });
-    }
+    private static native Thread[] getThreads();
 
     /**
      * Returns the identifier of this Thread.  The thread ID is a positive

runtime/openjdk.cs

@@ -3503,6 +3503,27 @@ namespace IKVM.NativeCode.java
 				return stackTrace.ToArray();
 #endif
 			}
+
+            public static object getThreads()
+            {
+#if FIRST_PASS
+				return null;
+#else
+                return global::java.security.AccessController.doPrivileged(global::ikvm.runtime.Delegates.toPrivilegedAction(delegate
+                {
+                    jlThreadGroup root = (jlThreadGroup)mainThreadGroup;
+                    for (; ; )
+                    {
+                        jlThread[] threads = new jlThread[root.activeCount()];
+                        if (root.enumerate(threads) == threads.Length)
+                        {
+                            return threads;
+                        }
+                    }
+                }));
+#endif
+            }
+			
 		}
 
 		static class ProcessImpl