[PresentationAPI] Implementing send() from WebPresentationClient to the PresentationService.

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;
 };
 
 enum PresentationErrorType {
     NO_AVAILABLE_SCREENS,
     SESSION_REQUEST_CANCELLED,
     NO_PRESENTATION_FOUND,
     UNKNOWN,
 };
 
 struct PresentationError {
     PresentationErrorType error_type;
     string message;
 };
 
+enum MessageType {

[imcheng, 2015/04/02 23:57:24]

Doesn't look like these are used. Remove them for now?

[USE s.singapati at gmail.com, 2015/04/07 17:45:16]

Done.

+    TEXT,
+    BINARY,
+};
+
+enum BinaryType {
+    NONE,
+    BLOB,
+    ARRAYBUFFER,
+};
+
 interface PresentationService {
     // Called when the frame sets or changes the default presentation URL or
     // presentation ID.
     SetDefaultPresentationURL(
         string default_presentation_url,
         string? default_presentation_id);
 
     // Returns the last screen availability state if it’s changed since the last
     // time the method was called. The client has to call this method again when
     // handling the result (provided via Mojo callback) to get the next update
@@ skipping 29 matching lines @@
     StartSession(string presentation_url, string? presentation_id)
         => (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 postMessage is called by the frame.
+    PostMessages(
+        string presentation_url,
+        string presentation_id,
+        array<string> string_messages);

[imcheng, 2015/04/02 23:57:24]

=> ();

This means PresentationDispatcher will supply a no-arg callback to be invoked by
PresentationServiceImpl to acknowledge that it has received the message and
ready for the next one.

[USE s.singapati at gmail.com, 2015/04/07 17:45:16]

Done.

+
     // Called when closeSession() is called by the frame.
     CloseSession(string presentation_url, string presentation_id);
 };