Execute callbacks from JS in the correct zone

sdk/lib/js/dart2js/js_dart2js.dart

 // Copyright (c) 2013, 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.
 
 /**
  * Support for interoperating with JavaScript.
  *
  * This library provides access to JavaScript objects from Dart, allowing
  * Dart code to get and set properties, and call methods of JavaScript objects
  * and invoke JavaScript functions. The library takes care of converting
@@ skipping 69 matching lines @@
  * `a` and `b` defined:
  *
  *     var jsMap = new JsObject.jsify({'a': 1, 'b': 2});
  *
  * This expression creates a JavaScript array:
  *
  *     var jsArray = new JsObject.jsify([1, 2, 3]);
  */
 library dart.js;
 
+import 'dart:async' show Zone;
 import 'dart:html' show Blob, Event, ImageData, Node, Window;
 import 'dart:collection' show HashMap, ListMixin;
 import 'dart:indexed_db' show KeyRange;
 import 'dart:typed_data' show TypedData;
 
 import 'dart:_foreign_helper' show JS, DART_CLOSURE_TO_JS;
 import 'dart:_interceptors' show JavaScriptObject, UnknownJavaScriptObject;
 import 'dart:_js_helper' show Primitives, convertDartClosureToJS,
     getIsolateAffinityTag;
 
 final JsObject context = _wrapToDart(Primitives.computeGlobalThis());
 
-_convertDartFunction(Function f, {bool captureThis: false}) {
+_convertDartFunction(Function f) {
   return JS('',
-    'function(_call, f, captureThis) {'
+    'function(_call, f) {'
       'return function() {'
-        'return _call(f, captureThis, this, '
-            'Array.prototype.slice.apply(arguments));'
+        'return _call(f, Array.prototype.slice.apply(arguments));'
       '}'
-    '}(#, #, #)', DART_CLOSURE_TO_JS(_callDartFunction), f, captureThis);
+    '}(#, #)', DART_CLOSURE_TO_JS(_callDartFunction), _applyZoned(f));
 }
 
-_callDartFunction(callback, bool captureThis, self, List arguments) {
-  if (captureThis) {
-    arguments = [self]..addAll(arguments);
-  }
-  var dartArgs = new List.from(arguments.map(_convertToDart));
-  return _convertToJS(Function.apply(callback, dartArgs));
+_convertDartFunctionWithThis(Function f) {
+  return JS('',
+    'function(_call, f) {'
+      'return function() {'
+        'var args = Array.prototype.slice.apply(arguments);'
+        'args.unshift(this);'
+        'return _call(f, args);'
+      '}'
+    '}(#, #)', DART_CLOSURE_TO_JS(_callDartFunction), _applyZoned(f));
+}
+
+_callDartFunction(f, List arguments) => f(arguments);
+
+_applyZoned(f) {
+  var callDart = (List arguments) {
+    var dartArgs = new List.from(arguments.map(_convertToDart));
+    return _convertToJS(Function.apply(f, dartArgs));
+  };
+  if (Zone.current == Zone.ROOT) return callDart;
+  return Zone.current.bindUnaryCallback(callDart);
 }
 
 /**
  * Proxies a JavaScript object to Dart.
  *
  * The properties of the JavaScript object are accessible via the `[]` and
  * `[]=` operators. Methods are callable via [callMethod].
  */
 class JsObject {
   // The wrapped JS object.
@@ skipping 188 matching lines @@
 /**
  * Proxies a JavaScript Function object.
  */
 class JsFunction extends JsObject {
 
   /**
    * Returns a [JsFunction] that captures its 'this' binding and calls [f]
    * with the value of this passed as the first argument.
    */
   factory JsFunction.withThis(Function f) {
-    var jsFunc = _convertDartFunction(f, captureThis: true);
+    var jsFunc = _convertDartFunctionWithThis(f);
     return new JsFunction._fromJs(jsFunc);
   }
 
   JsFunction._fromJs(jsObject) : super._fromJs(jsObject);
 
   /**
    * Invokes the JavaScript function with arguments [args]. If [thisArg] is
    * supplied it is the value of `this` for the invocation.
    */
   dynamic apply(List args, { thisArg }) =>
@@ skipping 236 matching lines @@
   // Dart in that context. The JS object will have a cached proxy
   // but it won't be a valid Dart object in this context.
   // For now we throw away the cached proxy, but we should be able
   // to cache proxies from multiple JS contexts and Dart isolates.
   if (dartProxy == null || !_isLocalObject(o)) {
     dartProxy = createProxy(o);
     _defineProperty(o, propertyName, dartProxy);
   }
   return dartProxy;
 }