Introduce very beginning of navigation

mojo/services/navigation/navigation.mojom

Index: mojo/services/navigation/navigation.mojom
diff --git a/mojo/services/navigation/navigation.mojom b/mojo/services/navigation/navigation.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..c09ff4e34496319b7c1ff7da930f986a10ec0349
--- /dev/null
+++ b/mojo/services/navigation/navigation.mojom
@@ -0,0 +1,18 @@
+// 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.
+
+module mojo.navigation {
+
+struct NavigationDetails {
+  string url;
+  // TODO(aa): method, data, etc.
+};
+
+// Applications implement this interface to support navigation of their views

[sky, 2014/06/10 22:15:14]

Your use of view here and below is confusing (and I think wrong). AFAICT you're
navigating the node. See EmbeddedAPp, where view_id is the id of the node. At a
minimum rename view_id (and update your description too). But you should also
consider renaming this to just Navigator.

[Aaron Boodman, 2014/06/10 22:31:31]

Ah, you are right, I started with view_id, but changed to node_id and forgot to
change here.

The interface name was intentional, but I see why you think it is confusing.
There is eventually going to be another interface, implemented by the embedder.
I was going to name this NodeNavigator (to parallel the Node/View relationship).

Anyway, I changed it to just Navigator for now.

+// by embedders.
+interface ViewNavigator {
+  Navigate(uint32 view_id, NavigationDetails details);
+};
+
+}