Convert UtilityProcessHost to bootstrap Mojo Channel using the Shell connection

content/browser/mojo/mojo_shell_context.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 CONTENT_BROWSER_MOJO_MOJO_SHELL_CONTEXT_H_
 #define CONTENT_BROWSER_MOJO_MOJO_SHELL_CONTEXT_H_
 
 #include <map>
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "base/compiler_specific.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/shell_context.h"
 #include "services/shell/public/interfaces/connector.mojom.h"
 #include "services/shell/shell.h"
 
 namespace catalog {
 class Catalog;
 }
 
 namespace shell {
 class ShellClient;
 }
 
 namespace content {
 
 // MojoShellContext hosts the browser's ApplicationManager, coordinating
 // app registration and interconnection.
-class CONTENT_EXPORT MojoShellContext {
+// TODO(beng): rename to ShellContextImpl.
+class CONTENT_EXPORT MojoShellContext : public ShellContext {
  public:
   MojoShellContext();
-  ~MojoShellContext();
+  ~MojoShellContext() override;
 
   // Connects an application at |name| and gets a handle to its exposed
   // services. This is only intended for use in browser code that's not part of
   // some Mojo application. May be called from any thread. |requestor_name| is
   // given to the target application as the requestor's name upon connection.
   static void ConnectToApplication(
       const std::string& user_id,
       const std::string& name,
       const std::string& requestor_name,
       shell::mojom::InterfaceProviderRequest request,
       shell::mojom::InterfaceProviderPtr exposed_services,
       const shell::mojom::Connector::ConnectCallback& callback);
 
-  // Returns a shell::Connector that can be used on the IO thread.
-  static shell::Connector* GetConnectorForIOThread();
-
  private:
   class BuiltinManifestProvider;
   class Proxy;
   friend class Proxy;
 
   void ConnectToApplicationOnOwnThread(
       const std::string& user_id,
       const std::string& name,
       const std::string& requestor_name,
       shell::mojom::InterfaceProviderRequest request,
       shell::mojom::InterfaceProviderPtr exposed_services,
       const shell::mojom::Connector::ConnectCallback& callback);
 
   static base::LazyInstance<std::unique_ptr<Proxy>> proxy_;
 
   std::unique_ptr<BuiltinManifestProvider> manifest_provider_;
   std::unique_ptr<catalog::Catalog> catalog_;
   std::unique_ptr<shell::Shell> shell_;
 
   DISALLOW_COPY_AND_ASSIGN(MojoShellContext);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MOJO_MOJO_SHELL_CONTEXT_H_