Extract shell methods from ApplicationImpl into a base class, and pass this to Initialize() instead.

mojo/shell/public/cpp/shell.h

+// Copyright 2016 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_SHELL_PUBLIC_CPP_SHELL_H_
+#define MOJO_SHELL_PUBLIC_CPP_SHELL_H_
+
+#include "mojo/shell/public/cpp/app_lifetime_helper.h"
+#include "mojo/shell/public/cpp/application_connection.h"
+#include "mojo/shell/public/interfaces/application.mojom.h"
+#include "mojo/shell/public/interfaces/shell.mojom.h"
+
+namespace mojo {
+
+shell::mojom::CapabilityFilterPtr CreatePermissiveCapabilityFilter();
+
+using ApplicationRequest = InterfaceRequest<shell::mojom::Application>;
+
+class Shell {
+ public:
+  class ConnectParams {
+   public:
+    explicit ConnectParams(const std::string& url);
+    explicit ConnectParams(URLRequestPtr request);
+    ~ConnectParams();
+
+    URLRequestPtr TakeRequest() { return std::move(request_); }
+    shell::mojom::CapabilityFilterPtr TakeFilter() {
+      return std::move(filter_);
+    }
+    void set_filter(shell::mojom::CapabilityFilterPtr filter) {
+      filter_ = std::move(filter);
+    }
+
+   private:
+    URLRequestPtr request_;
+    shell::mojom::CapabilityFilterPtr filter_;
+
+    DISALLOW_COPY_AND_ASSIGN(ConnectParams);
+  };
+
+  // Requests a new connection to an application. Returns a pointer to the
+  // connection if the connection is permitted by this application's delegate,
+  // or nullptr otherwise. Caller takes ownership.
+  virtual scoped_ptr<ApplicationConnection> ConnectToApplication(
+      const std::string& url) = 0;
+  virtual scoped_ptr<ApplicationConnection> ConnectToApplication(
+      ConnectParams* params) = 0;
+
+  // Connect to application identified by |request->url| and connect to the
+  // service implementation of the interface identified by |Interface|.
+  template <typename Interface>
+  void ConnectToService(ConnectParams* params, InterfacePtr<Interface>* ptr) {
+    scoped_ptr<ApplicationConnection> connection = ConnectToApplication(params);
+    if (!connection.get())
+      return;
+    connection->ConnectToService(ptr);
+  }
+  template <typename Interface>
+  void ConnectToService(const std::string& url, InterfacePtr<Interface>* ptr) {
+    ConnectParams params(url);
+    params.set_filter(CreatePermissiveCapabilityFilter());
+    return ConnectToService(&params, ptr);
+  }
+
+  // Initiate shutdown of this application. This may involve a round trip to the
+  // Shell to ensure there are no inbound service requests.
+  virtual void Quit() = 0;
+
+  // Create an object that can be used to refcount the lifetime of the
+  // application. The returned object may be cloned, and when the refcount falls
+  // to zero Quit() is called.
+  virtual scoped_ptr<AppRefCount> CreateAppRefCount() = 0;
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_SHELL_PUBLIC_CPP_SHELL_H_