Presentation API: ignore presentation id passed to startSession().

content/common/presentation/presentation_service.mojom

 // Copyright 2015 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 presentation;
 
 struct PresentationSessionInfo {
   string url;
   string id;
 };
@@ skipping 55 matching lines @@
   // session. If the default session is started by the embedder before this
   // call, the embedder may queue it and run the callback when the call is
   // performed.
   ListenForDefaultSessionStart()
       => (PresentationSessionInfo? defaultSessionInfo);
 
   // Called when startSession() is called by the frame. The result callback
   // will return a non-null and valid PresentationSessionInfo if starting the
   // session succeeded, or null with a PresentationError if starting the
   // session failed.
   // The presentation id is always returned along with the initialized

[whywhat, 2015/07/02 19:54:31]

Perhaps, you should mention that the presentation id is always generated by the
UA here?
I.e. replace the sentence with "The presentation id returned in |sessionInfo| on
success is generated by the UA."

[mlamouri (slow - plz ping), 2015/07/08 14:37:09]

Done.

   // session on success.
-  // If the UA identifies a matching session (same presentation url and id),
-  // the user may choose this existing session and the page will join it
-  // rather than get a new one. An empty presentation id means that the
-  // UA will generate the presentation id.
-  StartSession(string presentation_url, string? presentation_id)
+  // If the UA identifies a matching session (same presentation url), the user
+  // may choose this existing session and the page will join it rather than get
+  // a new one.
+  StartSession(string presentation_url)
       => (PresentationSessionInfo? sessionInfo, PresentationError? error);
 
   // Called when joinSession() is called by the frame. The result callback
   // works the same as for the method above. JoinSession will join a known
   // session (i.e. when the page navigates or the user opens another tab)
   // silently and without user action.
   JoinSession(string presentation_url, string? presentation_id)
       => (PresentationSessionInfo? sessionInfo, PresentationError? error);
 
   // Called when send() is called by the frame. The true in the
   // result callback notifies that the service is ready for next message.
   // The false in the result callback notifies the renderer to stop sending
   // the send requests and invalidate all pending requests. This occurs
   // for eg., when frame is deleted or navigated away.
   SendSessionMessage(SessionMessage message_request) => (bool success);
-  
+

[whywhat, 2015/07/02 19:54:31]

what's this diff?

[mlamouri (slow - plz ping), 2015/07/08 14:37:09]

Can't find that in my diff locally.

   // Called when closeSession() is called by the frame.
   CloseSession(string presentation_url, string presentation_id);
 
   // Called when the frame is ready to process the next state change. Returns
   // the last session state if it’s changed since the last time the callback
   // was called. Might cause the event fired with the initial state change.
   ListenForSessionStateChange()
       => (PresentationSessionInfo sessionInfo,
           PresentationSessionState newState);
 
   // Called when the frame is ready to process the next batch of messages.
   // When the callback carries null messages, there is an error
   // at the presentation service side.
   ListenForSessionMessages()
       => (array<SessionMessage>? messages);
 };
 
 interface PresentationServiceClient {
   OnScreenAvailabilityUpdated(bool available);
 };