| Index: mojo/dart/packages/mojo_services/lib/mojo/ui/view_trees.mojom.dart
 | 
| diff --git a/mojo/dart/packages/mojo_services/lib/mojo/ui/view_trees.mojom.dart b/mojo/dart/packages/mojo_services/lib/mojo/ui/view_trees.mojom.dart
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| index 9305800d2cde79ed2ccece6f02295daa5390acac..9e059f0958c3c820b2b55db926a16a1b23df190a 100644
 | 
| --- a/mojo/dart/packages/mojo_services/lib/mojo/ui/view_trees.mojom.dart
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| +++ b/mojo/dart/packages/mojo_services/lib/mojo/ui/view_trees.mojom.dart
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| @@ -20,6 +20,9 @@ class _ViewTreeGetTokenParams extends bindings.Struct {
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|  
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|    _ViewTreeGetTokenParams() : super(kVersions.last.size);
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|  
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| +  _ViewTreeGetTokenParams.init(
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| +  ) : super(kVersions.last.size);
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| +
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|    static _ViewTreeGetTokenParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -79,6 +82,10 @@ class ViewTreeGetTokenResponseParams extends bindings.Struct {
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|  
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|    ViewTreeGetTokenResponseParams() : super(kVersions.last.size);
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|  
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| +  ViewTreeGetTokenResponseParams.init(
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| +    view_tree_token_mojom.ViewTreeToken this.token
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| +  ) : super(kVersions.last.size);
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| +
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|    static ViewTreeGetTokenResponseParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -152,6 +159,10 @@ class _ViewTreeGetServiceProviderParams extends bindings.Struct {
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|  
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|    _ViewTreeGetServiceProviderParams() : super(kVersions.last.size);
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|  
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| +  _ViewTreeGetServiceProviderParams.init(
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| +    service_provider_mojom.ServiceProviderInterfaceRequest this.serviceProvider
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| +  ) : super(kVersions.last.size);
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| +
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|    static _ViewTreeGetServiceProviderParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -223,6 +234,10 @@ class _ViewTreeSetRendererParams extends bindings.Struct {
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|  
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|    _ViewTreeSetRendererParams() : super(kVersions.last.size);
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|  
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| +  _ViewTreeSetRendererParams.init(
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| +    renderers_mojom.RendererInterface this.renderer
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| +  ) : super(kVersions.last.size);
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| +
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|    static _ViewTreeSetRendererParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -294,6 +309,10 @@ class _ViewTreeGetContainerParams extends bindings.Struct {
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|  
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|    _ViewTreeGetContainerParams() : super(kVersions.last.size);
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|  
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| +  _ViewTreeGetContainerParams.init(
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| +    view_containers_mojom.ViewContainerInterfaceRequest this.container
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| +  ) : super(kVersions.last.size);
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| +
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|    static _ViewTreeGetContainerParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -364,6 +383,9 @@ class _ViewTreeListenerOnRendererDiedParams extends bindings.Struct {
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|  
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|    _ViewTreeListenerOnRendererDiedParams() : super(kVersions.last.size);
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|  
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| +  _ViewTreeListenerOnRendererDiedParams.init(
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| +  ) : super(kVersions.last.size);
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| +
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|    static _ViewTreeListenerOnRendererDiedParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -422,6 +444,9 @@ class ViewTreeListenerOnRendererDiedResponseParams extends bindings.Struct {
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|  
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|    ViewTreeListenerOnRendererDiedResponseParams() : super(kVersions.last.size);
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|  
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| +  ViewTreeListenerOnRendererDiedResponseParams.init(
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| +  ) : super(kVersions.last.size);
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| +
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|    static ViewTreeListenerOnRendererDiedResponseParams deserialize(bindings.Message message) {
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|      var decoder = new bindings.Decoder(message);
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|      var result = decode(decoder);
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| @@ -478,14 +503,17 @@ const int _viewTreeMethodSetRendererName = 2;
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|  const int _viewTreeMethodGetContainerName = 3;
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|  
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|  class _ViewTreeServiceDescription implements service_describer.ServiceDescription {
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| -  dynamic getTopLevelInterface([Function responseFactory]) =>
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| -      responseFactory(null);
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| +  void getTopLevelInterface(Function responder) {
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| +    responder(null);
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| +  }
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|  
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| -  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) =>
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| -      responseFactory(null);
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| +  void getTypeDefinition(String typeKey, Function responder) {
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| +    responder(null);
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| +  }
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|  
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| -  dynamic getAllTypeDefinitions([Function responseFactory]) =>
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| -      responseFactory(null);
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| +  void getAllTypeDefinitions(Function responder) {
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| +    responder(null);
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| +  }
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|  }
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|  
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|  abstract class ViewTree {
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| @@ -510,7 +538,7 @@ abstract class ViewTree {
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|      s.connectToService(url, p, name);
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|      return p;
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|    }
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| -  dynamic getToken([Function responseFactory = null]);
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| +  void getToken(void callback(view_tree_token_mojom.ViewTreeToken token));
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|    void getServiceProvider(service_provider_mojom.ServiceProviderInterfaceRequest serviceProvider);
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|    void setRenderer(renderers_mojom.RendererInterface renderer);
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|    void getContainer(view_containers_mojom.ViewContainerInterfaceRequest container);
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| @@ -563,18 +591,14 @@ class _ViewTreeProxyControl
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|            proxyError("Expected a message with a valid request Id.");
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|            return;
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|          }
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| -        Completer c = completerMap[message.header.requestId];
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| -        if (c == null) {
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| +        Function callback = callbackMap[message.header.requestId];
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| +        if (callback == null) {
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|            proxyError(
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|                "Message had unknown request Id: ${message.header.requestId}");
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|            return;
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|          }
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| -        completerMap.remove(message.header.requestId);
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| -        if (c.isCompleted) {
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| -          proxyError("Response completer already completed");
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| -          return;
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| -        }
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| -        c.complete(r);
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| +        callbackMap.remove(message.header.requestId);
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| +        callback(r.token );
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|          break;
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|        default:
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|          proxyError("Unexpected message type: ${message.header.type}");
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| @@ -619,16 +643,18 @@ class ViewTreeProxy
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|    }
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|  
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|  
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| -  dynamic getToken([Function responseFactory = null]) {
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| +  void getToken(void callback(view_tree_token_mojom.ViewTreeToken token)) {
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|      if (impl != null) {
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| -      return new Future(() => impl.getToken(_ViewTreeStubControl._viewTreeGetTokenResponseParamsFactory));
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| +      impl.getToken(callback);
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| +      return;
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|      }
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|      var params = new _ViewTreeGetTokenParams();
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| -    return ctrl.sendMessageWithRequestId(
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| +    ctrl.sendMessageWithRequestId(
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|          params,
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|          _viewTreeMethodGetTokenName,
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|          -1,
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| -        bindings.MessageHeader.kMessageExpectsResponse);
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| +        bindings.MessageHeader.kMessageExpectsResponse,
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| +        callback);
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|    }
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|    void getServiceProvider(service_provider_mojom.ServiceProviderInterfaceRequest serviceProvider) {
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|      if (impl != null) {
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| @@ -696,41 +722,31 @@ class _ViewTreeStubControl
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|    String get serviceName => ViewTree.serviceName;
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|  
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|  
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| -  static ViewTreeGetTokenResponseParams _viewTreeGetTokenResponseParamsFactory(view_tree_token_mojom.ViewTreeToken token) {
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| -    var result = new ViewTreeGetTokenResponseParams();
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| -    result.token = token;
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| -    return result;
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| +  Function _viewTreeGetTokenResponseParamsResponder(
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| +      int requestId) {
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| +  return (view_tree_token_mojom.ViewTreeToken token) {
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| +      var result = new ViewTreeGetTokenResponseParams();
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| +      result.token = token;
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| +      sendResponse(buildResponseWithId(
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| +          result,
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| +          _viewTreeMethodGetTokenName,
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| +          requestId,
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| +          bindings.MessageHeader.kMessageIsResponse));
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| +    };
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|    }
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|  
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| -  dynamic handleMessage(bindings.ServiceMessage message) {
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| +  void handleMessage(bindings.ServiceMessage message) {
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|      if (bindings.ControlMessageHandler.isControlMessage(message)) {
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| -      return bindings.ControlMessageHandler.handleMessage(this,
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| -                                                          0,
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| -                                                          message);
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| +      bindings.ControlMessageHandler.handleMessage(
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| +          this, 0, message);
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| +      return;
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|      }
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|      if (_impl == null) {
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|        throw new core.MojoApiError("$this has no implementation set");
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|      }
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|      switch (message.header.type) {
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|        case _viewTreeMethodGetTokenName:
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| -        var response = _impl.getToken(_viewTreeGetTokenResponseParamsFactory);
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| -        if (response is Future) {
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| -          return response.then((response) {
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| -            if (response != null) {
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| -              return buildResponseWithId(
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| -                  response,
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| -                  _viewTreeMethodGetTokenName,
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| -                  message.header.requestId,
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| -                  bindings.MessageHeader.kMessageIsResponse);
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| -            }
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| -          });
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| -        } else if (response != null) {
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| -          return buildResponseWithId(
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| -              response,
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| -              _viewTreeMethodGetTokenName,
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| -              message.header.requestId,
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| -              bindings.MessageHeader.kMessageIsResponse);
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| -        }
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| +        _impl.getToken(_viewTreeGetTokenResponseParamsResponder(message.header.requestId));
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|          break;
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|        case _viewTreeMethodGetServiceProviderName:
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|          var params = _ViewTreeGetServiceProviderParams.deserialize(
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| @@ -751,7 +767,6 @@ class _ViewTreeStubControl
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|          throw new bindings.MojoCodecError("Unexpected message name");
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|          break;
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|      }
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| -    return null;
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|    }
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|  
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|    ViewTree get impl => _impl;
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| @@ -805,8 +820,8 @@ class ViewTreeStub
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|    }
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|  
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|  
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| -  dynamic getToken([Function responseFactory = null]) {
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| -    return impl.getToken(responseFactory);
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| +  void getToken(void callback(view_tree_token_mojom.ViewTreeToken token)) {
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| +    return impl.getToken(callback);
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|    }
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|    void getServiceProvider(service_provider_mojom.ServiceProviderInterfaceRequest serviceProvider) {
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|      return impl.getServiceProvider(serviceProvider);
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| @@ -822,14 +837,17 @@ class ViewTreeStub
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|  const int _viewTreeListenerMethodOnRendererDiedName = 0;
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|  
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|  class _ViewTreeListenerServiceDescription implements service_describer.ServiceDescription {
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| -  dynamic getTopLevelInterface([Function responseFactory]) =>
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| -      responseFactory(null);
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| +  void getTopLevelInterface(Function responder) {
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| +    responder(null);
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| +  }
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|  
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| -  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) =>
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| -      responseFactory(null);
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| +  void getTypeDefinition(String typeKey, Function responder) {
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| +    responder(null);
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| +  }
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|  
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| -  dynamic getAllTypeDefinitions([Function responseFactory]) =>
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| -      responseFactory(null);
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| +  void getAllTypeDefinitions(Function responder) {
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| +    responder(null);
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| +  }
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|  }
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|  
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|  abstract class ViewTreeListener {
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| @@ -854,7 +872,7 @@ abstract class ViewTreeListener {
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|      s.connectToService(url, p, name);
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|      return p;
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|    }
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| -  dynamic onRendererDied([Function responseFactory = null]);
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| +  void onRendererDied(void callback());
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|  }
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|  
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|  abstract class ViewTreeListenerInterface
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| @@ -904,18 +922,14 @@ class _ViewTreeListenerProxyControl
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|            proxyError("Expected a message with a valid request Id.");
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|            return;
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|          }
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| -        Completer c = completerMap[message.header.requestId];
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| -        if (c == null) {
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| +        Function callback = callbackMap[message.header.requestId];
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| +        if (callback == null) {
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|            proxyError(
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|                "Message had unknown request Id: ${message.header.requestId}");
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|            return;
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|          }
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| -        completerMap.remove(message.header.requestId);
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| -        if (c.isCompleted) {
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| -          proxyError("Response completer already completed");
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| -          return;
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| -        }
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| -        c.complete(r);
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| +        callbackMap.remove(message.header.requestId);
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| +        callback();
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|          break;
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|        default:
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|          proxyError("Unexpected message type: ${message.header.type}");
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| @@ -960,16 +974,18 @@ class ViewTreeListenerProxy
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|    }
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|  
 | 
|  
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| -  dynamic onRendererDied([Function responseFactory = null]) {
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| +  void onRendererDied(void callback()) {
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|      if (impl != null) {
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| -      return new Future(() => impl.onRendererDied(_ViewTreeListenerStubControl._viewTreeListenerOnRendererDiedResponseParamsFactory));
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| +      impl.onRendererDied(callback);
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| +      return;
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|      }
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|      var params = new _ViewTreeListenerOnRendererDiedParams();
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| -    return ctrl.sendMessageWithRequestId(
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| +    ctrl.sendMessageWithRequestId(
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|          params,
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|          _viewTreeListenerMethodOnRendererDiedName,
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|          -1,
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| -        bindings.MessageHeader.kMessageExpectsResponse);
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| +        bindings.MessageHeader.kMessageExpectsResponse,
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| +        callback);
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|    }
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|  }
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|  
 | 
| @@ -995,46 +1011,35 @@ class _ViewTreeListenerStubControl
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|    String get serviceName => ViewTreeListener.serviceName;
 | 
|  
 | 
|  
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| -  static ViewTreeListenerOnRendererDiedResponseParams _viewTreeListenerOnRendererDiedResponseParamsFactory() {
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| -    var result = new ViewTreeListenerOnRendererDiedResponseParams();
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| -    return result;
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| +  Function _viewTreeListenerOnRendererDiedResponseParamsResponder(
 | 
| +      int requestId) {
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| +  return () {
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| +      var result = new ViewTreeListenerOnRendererDiedResponseParams();
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| +      sendResponse(buildResponseWithId(
 | 
| +          result,
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| +          _viewTreeListenerMethodOnRendererDiedName,
 | 
| +          requestId,
 | 
| +          bindings.MessageHeader.kMessageIsResponse));
 | 
| +    };
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|    }
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|  
 | 
| -  dynamic handleMessage(bindings.ServiceMessage message) {
 | 
| +  void handleMessage(bindings.ServiceMessage message) {
 | 
|      if (bindings.ControlMessageHandler.isControlMessage(message)) {
 | 
| -      return bindings.ControlMessageHandler.handleMessage(this,
 | 
| -                                                          0,
 | 
| -                                                          message);
 | 
| +      bindings.ControlMessageHandler.handleMessage(
 | 
| +          this, 0, message);
 | 
| +      return;
 | 
|      }
 | 
|      if (_impl == null) {
 | 
|        throw new core.MojoApiError("$this has no implementation set");
 | 
|      }
 | 
|      switch (message.header.type) {
 | 
|        case _viewTreeListenerMethodOnRendererDiedName:
 | 
| -        var response = _impl.onRendererDied(_viewTreeListenerOnRendererDiedResponseParamsFactory);
 | 
| -        if (response is Future) {
 | 
| -          return response.then((response) {
 | 
| -            if (response != null) {
 | 
| -              return buildResponseWithId(
 | 
| -                  response,
 | 
| -                  _viewTreeListenerMethodOnRendererDiedName,
 | 
| -                  message.header.requestId,
 | 
| -                  bindings.MessageHeader.kMessageIsResponse);
 | 
| -            }
 | 
| -          });
 | 
| -        } else if (response != null) {
 | 
| -          return buildResponseWithId(
 | 
| -              response,
 | 
| -              _viewTreeListenerMethodOnRendererDiedName,
 | 
| -              message.header.requestId,
 | 
| -              bindings.MessageHeader.kMessageIsResponse);
 | 
| -        }
 | 
| +        _impl.onRendererDied(_viewTreeListenerOnRendererDiedResponseParamsResponder(message.header.requestId));
 | 
|          break;
 | 
|        default:
 | 
|          throw new bindings.MojoCodecError("Unexpected message name");
 | 
|          break;
 | 
|      }
 | 
| -    return null;
 | 
|    }
 | 
|  
 | 
|    ViewTreeListener get impl => _impl;
 | 
| @@ -1088,8 +1093,8 @@ class ViewTreeListenerStub
 | 
|    }
 | 
|  
 | 
|  
 | 
| -  dynamic onRendererDied([Function responseFactory = null]) {
 | 
| -    return impl.onRendererDied(responseFactory);
 | 
| +  void onRendererDied(void callback()) {
 | 
| +    return impl.onRendererDied(callback);
 | 
|    }
 | 
|  }
 | 
|  
 | 
| 
 |