Fix hangs in Mandoline page cycler on Linux with --enable-multiprocess.

components/html_viewer/layout_test_content_handler_impl.cc

 // Copyright 2015 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.
 
 #include "components/html_viewer/layout_test_content_handler_impl.h"
 
 #include "base/bind.h"
 #include "components/html_viewer/global_state.h"
 #include "components/html_viewer/html_document_application_delegate.h"
 #include "components/html_viewer/html_widget.h"
@@ skipping 34 matching lines @@
 
 LayoutTestContentHandlerImpl::LayoutTestContentHandlerImpl(
     GlobalState* global_state,
     mojo::ApplicationImpl* app,
     mojo::InterfaceRequest<mojo::ContentHandler> request,
     test_runner::WebTestInterfaces* test_interfaces,
     WebTestDelegateImpl* test_delegate)
     : ContentHandlerImpl(global_state, app, request.Pass()),
       test_interfaces_(test_interfaces),
       test_delegate_(test_delegate),
-      web_widget_proxy_(nullptr) {}
+      web_widget_proxy_(nullptr),
+      app_refcount_(app->app_lifetime_helper()->CreateAppRefCount()) {}
 
 LayoutTestContentHandlerImpl::~LayoutTestContentHandlerImpl() {
 }
 
 void LayoutTestContentHandlerImpl::StartApplication(
     mojo::InterfaceRequest<mojo::Application> request,
-    mojo::URLResponsePtr response) {
+    mojo::URLResponsePtr response,
+    const mojo::Callback<void()>& destruct_callback) {
   test_interfaces_->SetTestIsRunning(true);
   test_interfaces_->ConfigureForTestWithURL(GURL(), false);
 
   // HTMLDocumentApplicationDelegate deletes itself.
   HTMLDocumentApplicationDelegate* delegate =
       new HTMLDocumentApplicationDelegate(
           request.Pass(), response.Pass(), global_state(),
-          app()->app_lifetime_helper()->CreateAppRefCount());
+          app()->app_lifetime_helper()->CreateAppRefCount(),
+          destruct_callback);
 
   delegate->set_html_factory(this);
 }
 
 HTMLWidgetRootLocal* LayoutTestContentHandlerImpl::CreateHTMLWidgetRootLocal(
     HTMLWidgetRootLocal::CreateParams* params) {
   web_widget_proxy_ = new WebWidgetProxy(params);
   return web_widget_proxy_;
 }
 
@@ skipping 17 matching lines @@
   proxy->set_base_proxy(web_widget_proxy_);
   test_delegate_->set_test_proxy(web_widget_proxy_);
   test_interfaces_->SetWebView(web_widget_proxy_->web_view(),
                                web_widget_proxy_);
   web_widget_proxy_->set_widget(web_widget_proxy_->web_view());
   test_interfaces_->BindTo(web_widget_proxy_->web_view()->mainFrame());
   return proxy;
 }
 
 }  // namespace html_viewer