Revert of Remove shell::Loader

services/shell/shell.h

 // Copyright 2014 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 SERVICES_SHELL_SHELL_H_
 #define SERVICES_SHELL_SHELL_H_
 
 #include <map>
 #include <memory>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "mojo/public/cpp/bindings/interface_ptr_set.h"
 #include "services/shell/connect_params.h"
+#include "services/shell/loader.h"
 #include "services/shell/native_runner.h"
 #include "services/shell/public/cpp/capabilities.h"
 #include "services/shell/public/cpp/identity.h"
 #include "services/shell/public/cpp/interface_factory.h"
 #include "services/shell/public/cpp/shell_client.h"
 #include "services/shell/public/interfaces/connector.mojom.h"
 #include "services/shell/public/interfaces/interface_provider.mojom.h"
 #include "services/shell/public/interfaces/shell.mojom.h"
 #include "services/shell/public/interfaces/shell_client.mojom.h"
 #include "services/shell/public/interfaces/shell_client_factory.mojom.h"
@@ skipping 19 matching lines @@
    private:
     Shell* shell_;
 
     DISALLOW_COPY_AND_ASSIGN(TestAPI);
   };
 
   // |native_runner_factory| is an instance of an object capable of vending
   // implementations of NativeRunner, e.g. for in or out-of-process execution.
   // See native_runner.h and RunNativeApplication().
   // |file_task_runner| provides access to a thread to perform file copy
-  // operations on.
+  // operations on. This may be null only in testing environments where
+  // applications are loaded via Loader implementations.
   Shell(std::unique_ptr<NativeRunnerFactory> native_runner_factory,
         mojom::ShellClientPtr catalog);
   ~Shell() override;
 
   // Provide a callback to be notified whenever an instance is destroyed.
   // Typically the creator of the Shell will use this to determine when some set
   // of instances it created are destroyed, so it can shut down.
   void SetInstanceQuitCallback(base::Callback<void(const Identity&)> callback);
 
   // Completes a connection between a source and target application as defined
   // by |params|, exchanging InterfaceProviders between them. If no existing
   // instance of the target application is running, one will be loaded.
   void Connect(std::unique_ptr<ConnectParams> params);
 
   // Creates a new Instance identified as |name|. This is intended for use by
   // the Shell's embedder to register itself with the shell. This must only be
   // called once.
   mojom::ShellClientRequest InitInstanceForEmbedder(const std::string& name);
 
+  // Sets the default Loader to be used if not overridden by SetLoaderForName().
+  void set_default_loader(std::unique_ptr<Loader> loader) {
+    default_loader_ = std::move(loader);
+  }
+
+  // Sets a Loader to be used for a specific name.
+  void SetLoaderForName(std::unique_ptr<Loader> loader,
+                        const std::string& name);
+
  private:
   class Instance;
 
   // ShellClient:
   bool AcceptConnection(Connection* connection) override;
 
   void InitCatalog(mojom::ShellClientPtr catalog);
 
   // Destroys all Shell-ends of connections established with Applications.
   // Applications connected by this Shell will observe pipe errors and have a
@@ skipping 43 matching lines @@
   // Callback when remote Catalog resolves mojo:foo to mojo:bar.
   // |params| are the params passed to Connect().
   // |client| if provided is a ShellClientPtr which should be used to manage the
   // new application instance. This may be null.
   // |result| contains the result of the resolve operation.
   void OnGotResolvedName(mojom::ShellResolverPtr resolver,
                          std::unique_ptr<ConnectParams> params,
                          mojom::ShellClientPtr client,
                          mojom::ResolveResultPtr result);
 
+  // Tries to load |target| with an Loader. Returns true if one was registered
+  // and it was loaded, in which case |request| is taken.
+  bool LoadWithLoader(const Identity& target,
+                      mojom::ShellClientRequest* request);
+
+  // Returns the appropriate loader for |name|, or the default loader if there
+  // is no loader configured for the name.
+  Loader* GetLoaderForName(const std::string& name);
+
   base::WeakPtr<Shell> GetWeakPtr();
 
   void CleanupRunner(NativeRunner* runner);
 
+  // Loader management.
+  // Loaders are chosen in the order they are listed here.
+  std::map<std::string, Loader*> name_to_loader_;
+  std::unique_ptr<Loader> default_loader_;
+
   std::map<Identity, Instance*> identity_to_instance_;
 
   // Tracks the names of instances that are allowed to field connection requests
   // from all users.
   std::set<std::string> singletons_;
 
   std::map<Identity, mojom::ShellClientFactoryPtr> shell_client_factories_;
   // Counter used to assign ids to client factories.
   uint32_t shell_client_factory_id_counter_;
 
   mojo::InterfacePtrSet<mojom::InstanceListener> instance_listeners_;
 
   base::Callback<void(const Identity&)> instance_quit_callback_;
   std::unique_ptr<NativeRunnerFactory> native_runner_factory_;
   std::vector<std::unique_ptr<NativeRunner>> native_runners_;
   std::unique_ptr<ShellConnection> shell_connection_;
   base::WeakPtrFactory<Shell> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
 
 mojom::Connector::ConnectCallback EmptyConnectCallback();
 
 }  // namespace shell
 
 #endif  // SERVICES_SHELL_SHELL_H_