Mojo: Use InterfaceFactory<Interface> for service registration

mojo/public/cpp/application/context_interface_factory.h

Index: mojo/public/cpp/application/context_interface_factory.h
diff --git a/mojo/public/cpp/application/context_interface_factory.h b/mojo/public/cpp/application/context_interface_factory.h
new file mode 100644
index 0000000000000000000000000000000000000000..9e9aad1fba139a4658984970aeaaad785670da8d
--- /dev/null
+++ b/mojo/public/cpp/application/context_interface_factory.h
@@ -0,0 +1,33 @@
+// 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 MOJO_PUBLIC_CPP_APPLICATION_CONTEXT_INTERFACE_FACTORY_H_
+#define MOJO_PUBLIC_CPP_APPLICATION_CONTEXT_INTERFACE_FACTORY_H_
+
+#include "mojo/public/cpp/application/interface_factory.h"
+
+namespace mojo {
+
+// Use this class to allocate and bind instances of Impl constructed with a
+// context parameter response to requests for interface Interface.

[darin (slow to review), 2014/07/15 06:10:37]

nit: seems like a period belongs after "parameter", but then I'm having trouble
parsing the remaining bit of the comment.

+template <typename Impl,
+          typename Context,
+          typename Interface = typename Impl::Implements>
+class ContextInterfaceFactory : public InterfaceFactory<Interface> {

[darin (slow to review), 2014/07/15 06:10:38]

nit: How about renaming this to InterfaceFactoryWithContext?
ContextInterfaceFactory sounds like the name of a "factory of context
interfaces", but I'm not sure what a "context interface" is. This class is
constructed with a Context* parameter, so saying that it is an "interface
factory with context" makes a bit of sense.

+ public:
+  explicit ContextInterfaceFactory(Context* context) : context_(context) {}
+  virtual ~ContextInterfaceFactory() {}
+
+  virtual void Create(ApplicationConnection* connection,
+                      InterfaceRequest<Interface> request) MOJO_OVERRIDE {
+    mojo::BindToRequest(new Impl(context_), &request);
+  }
+
+ private:
+  Context* context_;
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_PUBLIC_CPP_APPLICATION_CONTEXT_INTERFACE_FACTORY_H_