Simple multi-url support for mojo apps

mojo/public/interfaces/application/application.mojom

Index: mojo/public/interfaces/application/application.mojom
diff --git a/mojo/public/interfaces/application/application.mojom b/mojo/public/interfaces/application/application.mojom
index 03fe94369dcfd5ec6ff19571fff240e142bc3038..857823669f2f978376945de85a103d50f38461e3 100644
--- a/mojo/public/interfaces/application/application.mojom
+++ b/mojo/public/interfaces/application/application.mojom
@@ -10,6 +10,9 @@ import "mojo/public/interfaces/application/shell.mojom";
 // This is the primary interface implemented by every Mojo application. It
 // allows the application to receive its startup arguments from the shell, and
 // to be notified of events that occur during its execution.
+//
+// TODO(aa): It would be good to reorder the parameters once we have interface
+// versioning.
 interface Application {
   // Initializes the application with the specified arguments. This method is
   // guaranteed to be called before any other method is called, and will only be
@@ -37,9 +40,14 @@ interface Application {
   //
   // This application is free to ignore the |services| or |exposed_services|
   // parameters if it does not wish to offer or request services.
+  //
+  // resolved_url is the URL that was requested after all resolutions and
+  // redirects. This can be different than the URL this application was actually
+  // found at, if the application is handling multiple URLs.

[qsr, 2015/02/27 17:15:58]

Did you try putting resolved_url first, then annotation each thing with
[MinVersion=X] where X is 1,2 3 for the existing parameter, and 4 for the last
one.

I think this should be equivalent as this one on the write, but will generate
the code in the right order.

[Aaron Boodman, 2015/02/28 19:08:23]

I tried, it doesn't seem to be fully implemented. Results in validation errors.
I also talked to Yuzhu and he said there was no way to get the params in right
order right now.

   AcceptConnection(string requestor_url,
                    ServiceProvider&? services,
-                   ServiceProvider? exposed_services);
+                   ServiceProvider? exposed_services,
+                   string resolved_url);
 
   // Called to request the application shut itself down gracefully.
   RequestQuit();