8011023: Math round didn't conform to ECMAScript 5 spec

Reviewed-by: jlaskey, attila

nashorn/src/jdk/nashorn/internal/objects/NativeMath.java

@@ -611,13 +611,11 @@ public final class NativeMath extends ScriptObject {
      */
     @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
     public static Object round(final Object self, final Object x) {
-        if (GlobalFunctions.isNaN(self, x)) {
-            return Double.NaN;
-        } else if (!GlobalFunctions.isFinite(self, x)) {
-            return x;
+        final double d = JSType.toNumber(x);
+        if (Math.getExponent(d) >= 52) {
+            return d;
         }
-
-        return Math.round(JSType.toNumber(x));
+        return Math.copySign(Math.floor(d + 0.5), d);
     }
 
     /**

nashorn/test/script/basic/JDK-8011023.js

+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * Round should be ecma compliant
+ *
+ * @test
+ * @run 
+ */
+
+print(1/Math.round(-0.5));
+print(Math.round(9007199254740991));
+print(Math.round(9223372036854775807*2));
+

nashorn/test/script/basic/JDK-8011023.js.EXPECTED

+-Infinity
+9007199254740991
+18446744073709552000