fixes dart.throw to work for non-objects

test/browser/runtime_tests.js

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 var assert = chai.assert;
 var core = dart_library.import('dart/core');
 var collection = dart_library.import('dart/collection');
 var dart = dart_library.import('dart_runtime/dart');
 var dartx = dart.dartx;
 
 // TODO(leafp): These are here to test some things not
 // currently exposed through the main dart entry point.
 // If we decide to expose them, this can go away.
 var classes = dart_library.import('dart_runtime/_classes');
 var types = dart_library.import('dart_runtime/_types');
 
 suite('generic', () => {
   "use strict";
 
   let generic = dart.generic;
 
   test('zero arguments is not allowed', () => {
     assert.throws(() => { generic(function(){}); });
   });
 
+  test('can throw number', () => {
+    try {
+      dart.throw(42);
+    } catch (e) {
+      assert.equal(e, 42);
+    }
+  });
+
   test('argument count cannot change', () => {
     let SomeType = generic(function(x) { return {x: x}; });
     assert.throws(() => { SomeType(1,2) });
     let obj = {};
     assert.equal(SomeType(obj).x, obj);
     assert.equal(SomeType(obj).x, obj);
     assert.equal(SomeType().x, dart.dynamic);
   });
 
   test('undefined/null are not allowed', () => {
@@ skipping 693 matching lines @@
 
 suite('primitives', function() {
   'use strict';
 
   test('fixed length list', () => {
     let list = new core.List(10);
     list[0] = 42;
     assert.throws(() => list.add(42));
   });
 });