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

mojo/package_manager/content_handler_connection.h

 // 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.
 
 #ifndef MOJO_PACKAGE_MANAGER_CONTENT_HANDLER_CONNECTION_H_
 #define MOJO_PACKAGE_MANAGER_CONTENT_HANDLER_CONNECTION_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 16 matching lines @@
 class ContentHandlerConnection {
  public:
   using ClosedCallback = base::Callback<void(ContentHandlerConnection*)>;
   // |id| is a unique identifier for this content handler.
   ContentHandlerConnection(shell::ApplicationManager* manager,
                            const shell::Identity& source,
                            const shell::Identity& content_handler,
                            uint32_t id,
                            const ClosedCallback& connection_closed_callback);
 
+  void StartApplication(InterfaceRequest<Application> request,
+                        URLResponsePtr response);
+
   // Closes the connection and destroys |this| object.
   void CloseConnection();
 
-  ContentHandler* content_handler() { return content_handler_.get(); }
   const shell::Identity& identity() const { return identity_; }
   uint32_t id() const { return id_; }
 
  private:
   ~ContentHandlerConnection();
 
+  void ApplicationDestructed();
+
   ClosedCallback connection_closed_callback_;
   shell::Identity identity_;
 
   ContentHandlerPtr content_handler_;
   bool connection_closed_;
   // The id for this content handler.
   const uint32_t id_;
+  int ref_count_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentHandlerConnection);
 };
 
 }  // namespace package_manager
 }  // namespace mojo
 
 #endif  // MOJO_PACKAGE_MANAGER_CONTENT_HANDLER_CONNECTION_H_