[Presentation API] (3rd) (1-UA) Split PresentationServiceDelegateImpl(PSDImpl)

third_party/WebKit/public/platform/modules/presentation/presentation.mojom

Index: third_party/WebKit/public/platform/modules/presentation/presentation.mojom
diff --git a/third_party/WebKit/public/platform/modules/presentation/presentation.mojom b/third_party/WebKit/public/platform/modules/presentation/presentation.mojom
index ec0f087bcb93904d144e91c6bc7da79d8b9e011e..d5f6dcdc43facd8857fe331432cd22173323606e 100644
--- a/third_party/WebKit/public/platform/modules/presentation/presentation.mojom
+++ b/third_party/WebKit/public/platform/modules/presentation/presentation.mojom
@@ -52,10 +52,24 @@ struct SessionMessage {
   array<uint8>? data;
 };
 
+interface PresentationConnection {
+   // TODO(zhaobin): migrate SendSessionMessage from PresentationService =>
+   // PresentationConnection.Send(). http://crbug.com/658474
+
+   // Called to set the PresentationConnection that is the destination for
+   // messages sent and the source of messages received by this connection.
+   SetTargetConnection(PresentationConnection connection);
+
+   // Called when a message is sent by the target connection.
+   OnMessage(SessionMessage message);
+};
+
 interface PresentationService {
   // Sets the PresentationServiceClient.
   SetClient(PresentationServiceClient client);
 
+  ///////////// Functions here are for the controller part of the API. /////////
+
   // Called when the frame sets or changes the default presentation URLs.
   // When the default presentation is started on this frame,
   // PresentationServiceClient::OnDefaultSessionStarted will be invoked.
@@ -90,6 +104,14 @@ interface PresentationService {
   JoinSession(array<url.mojom.Url> presentation_urls, string? presentation_id)
       => (PresentationSessionInfo? sessionInfo, PresentationError? error);
 
+  // Called in StartSession's callback function for offscreen presentation only.
+  // It passes in controlling frame's PresentationConnection to
+  // PresentationService.
+  SetPresentationConnection(PresentationSessionInfo sessionInfo,
+                            PresentationConnection connection);
+
+  //////////////////////////////////////////////////////////////////////////////
+
   // 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