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

mojo/package_manager/content_handler_connection.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 "mojo/package_manager/content_handler_connection.h"
 
+#include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "mojo/shell/application_manager.h"
 #include "mojo/shell/connect_to_application_params.h"
 #include "mojo/shell/identity.h"
 
 namespace mojo {
 namespace package_manager {
 
 ContentHandlerConnection::ContentHandlerConnection(
     shell::ApplicationManager* manager,
     const shell::Identity& source,
     const shell::Identity& content_handler,
     uint32_t id,
     const ClosedCallback& connection_closed_callback)
     : connection_closed_callback_(connection_closed_callback),
       identity_(content_handler),
       connection_closed_(false),
-      id_(id) {
+      id_(id),
+      ref_count_(0) {
   ServiceProviderPtr services;
 
   scoped_ptr<shell::ConnectToApplicationParams> params(
       new shell::ConnectToApplicationParams);
   params->set_source(source);
   params->SetTarget(identity_);
   params->set_services(GetProxy(&services));
   manager->ConnectToApplication(params.Pass());
 
   MessagePipe pipe;
   content_handler_.Bind(
       InterfacePtrInfo<ContentHandler>(pipe.handle0.Pass(), 0u));
   services->ConnectToService(ContentHandler::Name_, pipe.handle1.Pass());
   content_handler_.set_connection_error_handler(
       [this]() { CloseConnection(); });
 }
 
+void ContentHandlerConnection::StartApplication(
+    InterfaceRequest<Application> request,
+    URLResponsePtr response) {
+  content_handler_->StartApplication(
+      request.Pass(), response.Pass(),
+      base::Bind(&ContentHandlerConnection::ApplicationDestructed,
+                 base::Unretained(this)));
+  ref_count_++;
+}
+
 void ContentHandlerConnection::CloseConnection() {
   if (connection_closed_)
     return;
   connection_closed_ = true;
   connection_closed_callback_.Run(this);
   delete this;
 }
 
 ContentHandlerConnection::~ContentHandlerConnection() {
   // If this DCHECK fails then something has tried to delete this object without
   // calling CloseConnection.
   DCHECK(connection_closed_);
 }
 
+void ContentHandlerConnection::ApplicationDestructed() {
+  if (!--ref_count_)
+    CloseConnection();
+}
+
 }  // namespace package_manager
 }  // namespace mojo