[Presentation API] Change ListenForSessionMessages API to client-style.

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 15 matching lines @@
   string message;
 };
 
 enum PresentationMessageType {
   TEXT,
   ARRAY_BUFFER,
   BLOB,
 };
 
 struct SessionMessage {
-  string presentation_url;
-  string presentation_id;
   PresentationMessageType type;
   // Used when message type is TEXT.
   string? message;
   // Used when message type is ARRAY_BUFFER or BLOB.
   array<uint8>? data;
 };
 
 interface PresentationService {
   // Called when the frame sets or changes the default presentation URL.
   SetDefaultPresentationURL(string url);
@@ skipping 35 matching lines @@
   // 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);
+  SendSessionMessage(PresentationSessionInfo sessionInfo, SessionMessage message_request) => (bool success);
 
   // Called when closeSession() is called by the frame.
   CloseSession(string presentation_url, string presentation_id);
 
   // Starts listening for state changes for sessions created on this frame.
   // When state change occurs, PresentationServiceClient::OnSessionStateChanged
   // will be invoked with the session and its new state.
+  // This is called after a presentation session is created.
   ListenForSessionStateChange();
 
-  // 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);
+  // Starts listening for messages for session with |sessionInfo|.
+  // Messages will be received in
+  // PresentationServiceClient::OnSessionMessagesReceived.
+  // This is called after a presentation session is created.
+  ListenForSessionMessages(PresentationSessionInfo sessionInfo);
 };
 
 interface PresentationServiceClient {
   // Called when the client tries to listen for screen availability changes but
   // it is not supported by the device or underlying platform. This can also be
   // called if the device is currently in a mode where it can't do screen
   // discoveries (eg. low battery).
   OnScreenAvailabilityNotSupported();
 
   // Called when the client is listening for screen availability and the state
   // changes. When the client starts to listen for screen availability, this
   // method will always be called to give the current known state. It will then
   // be called to notify of state updates.
   OnScreenAvailabilityUpdated(bool available);
 
   // See PresentationService::ListenForSessionStateChange.
   OnSessionStateChanged(PresentationSessionInfo sessionInfo,
                         PresentationSessionState newState);
+
+  // See PresentationService::ListenForSessionMessages.
+  OnSessionMessagesReceived(PresentationSessionInfo sessionInfo, array<SessionMessage> messages);
 };