Dart: Removes need to call listen().

mojo/public/dart/src/application.dart

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 part of application;
 
 class _ApplicationImpl implements application_mojom.Application {
   application_mojom.ApplicationStub _stub;
   shell_mojom.ShellProxy shell;
   Application _application;
 
-  _ApplicationImpl(Application application,
-      core.MojoMessagePipeEndpoint endpoint, {Function onClosed}) {
+  _ApplicationImpl(
+      Application application, core.MojoMessagePipeEndpoint endpoint) {
     _application = application;
-    // We wrap the onClosed callback in a closure to ensure that all
-    // necessary cleanup is performed on a PEER_CLOSED signal.
-    _stub = new application_mojom.ApplicationStub.fromEndpoint(
-        endpoint,
-        impl: this,
-        onClosed: _closer(onClosed));
+    _stub = new application_mojom.ApplicationStub.fromEndpoint(endpoint, this);
+    _stub.onError = close;
   }
 
-  _ApplicationImpl.fromHandle(Application application, core.MojoHandle handle,
-      {Function onClosed}) {
+  _ApplicationImpl.fromHandle(Application application, core.MojoHandle handle) {
     _application = application;
-    _stub = new application_mojom.ApplicationStub.fromHandle(
-        handle,
-        impl: this,
-        onClosed: _closer(onClosed));
+    _stub = new application_mojom.ApplicationStub.fromHandle(handle, this);
+    _stub.onError = close;
   }
 
-  void initialize(bindings.ProxyBase shellProxy, List<String> args,
-      String url) {
+  set onError(core.ErrorHandler f) {
+    _stub.onError = f;
+  }
+
+  void initialize(
+      bindings.ProxyBase shellProxy, List<String> args, String url) {
     assert(shell == null);
     shell = shellProxy;
     _application.initialize(args, url);
   }
 
   @override
   void acceptConnection(String requestorUrl, ServiceProviderStub services,
-      bindings.ProxyBase exposedServices, String resolvedUrl) =>
-      _application._acceptConnection(
-          requestorUrl,
-          services,
-          exposedServices,
-          resolvedUrl);
+      bindings.ProxyBase exposedServices, String resolvedUrl) => _application
+      ._acceptConnection(requestorUrl, services, exposedServices, resolvedUrl);
 
   @override
   void requestQuit() => _application._requestQuitAndClose();
 
-  Function _closer(Function onClosed) {
-    return (() {
-      if (onClosed != null) {
-        onClosed();
-      }
-      close();
-    });
-  }
-
   void close({bool nodefer: false}) {
-    shell.close();
+    if (shell != null) shell.close();
     _stub.close();
   }
 }
 
 // TODO(zra): Better documentation and examples.
 // To implement, do the following:
 // - Optionally override initialize() to process command-line args.
 // - Optionally override acceptConnection() if services are to be provided.
 // - Optionally override close() to clean up application resources.
 abstract class Application {
   _ApplicationImpl _applicationImpl;
   List<ApplicationConnection> _applicationConnections;
 
-  Application(core.MojoMessagePipeEndpoint endpoint, {Function onClosed}) {
+  Application(core.MojoMessagePipeEndpoint endpoint) {
     _applicationConnections = [];
-    // We wrap the onClosed callback in a closure to ensure that all
-    // necessary cleanup is performed on a PEER_CLOSED signal.
-    _applicationImpl =
-        new _ApplicationImpl(this, endpoint, onClosed: _closer(onClosed));
+    _applicationImpl = new _ApplicationImpl(this, endpoint);
+    _applicationImpl.onError = close;
   }
 
-  Application.fromHandle(core.MojoHandle appHandle, {Function onClosed}) {
+  Application.fromHandle(core.MojoHandle appHandle) {
     _applicationConnections = [];
-    _applicationImpl =
-        new _ApplicationImpl.fromHandle(this, appHandle, onClosed: _closer(onClosed));
+    _applicationImpl = new _ApplicationImpl.fromHandle(this, appHandle);
+    _applicationImpl.onError = close;
   }
 
   void initialize(List<String> args, String url) {}
 
   // TODO(skydart): This is a temporary fix to allow sky application to consume
   // mojo services. Do not use for any other purpose.
-  void initializeFromShellProxy(shell_mojom.ShellProxy shellProxy,
-      List<String> args, String url) =>
+  void initializeFromShellProxy(
+          shell_mojom.ShellProxy shellProxy, List<String> args, String url) =>
       _applicationImpl.initialize(shellProxy, args, url);
 
   // Returns a connection to the app at |url|.
   ApplicationConnection connectToApplication(String url) {
     var proxy = new ServiceProviderProxy.unbound();
     var stub = new ServiceProviderStub.unbound();
     _applicationImpl.shell.ptr.connectToApplication(url, proxy, stub);
     var connection = new ApplicationConnection(stub, proxy);
     _applicationConnections.add(connection);
     return connection;
   }
 
   void connectToService(String url, bindings.ProxyBase proxy) {
     connectToApplication(url).requestService(proxy);
   }
 
   void requestQuit() {}
 
   void _requestQuitAndClose() {
     requestQuit();
     close();
   }
 
-  Function _closer(Function onClose) {
-    return (() {
-      if (onClose != null) {
-        onClose();
-      }
-      close();
-    });
-  }
-
   void close() {
     assert(_applicationImpl != null);
     _applicationConnections.forEach((c) => c.close());
     _applicationConnections.clear();
     _applicationImpl.close();
   }
 
   // This method closes all the application connections. Used during apptesting.
-  resetConnections() {
+  void resetConnections() {
     assert(_applicationImpl != null);
     _applicationConnections.forEach((c) => c.close());
     _applicationConnections.clear();
   }
 
   void _acceptConnection(String requestorUrl, ServiceProviderStub services,
       ServiceProviderProxy exposedServices, String resolvedUrl) {
     var connection = new ApplicationConnection(services, exposedServices);
     _applicationConnections.add(connection);
     acceptConnection(requestorUrl, resolvedUrl, connection);
   }
 
   // Override this method to provide services on |connection|.
-  // If you provide at least one service or set fallbackServiceProvider,
-  // then you must invoke connection.listen().
   void acceptConnection(String requestorUrl, String resolvedUrl,
-      ApplicationConnection connection) {
-  }
+      ApplicationConnection connection) {}
 }