Implements ListenForSessionMessages in PresentationServiceImpl; uses Swap to avoid copying large da…

content/browser/presentation/presentation_service_impl.h

Index: content/browser/presentation/presentation_service_impl.h
diff --git a/content/browser/presentation/presentation_service_impl.h b/content/browser/presentation/presentation_service_impl.h
index fd85fe8f3444207f03aca3fe1093b846633894df..282fcc3ed56e499eda2fdfc9bf84d7297e0a3952 100644
--- a/content/browser/presentation/presentation_service_impl.h
+++ b/content/browser/presentation/presentation_service_impl.h
@@ -28,6 +28,7 @@ namespace content {
 
 struct FrameNavigateParams;
 struct LoadCommittedDetails;
+struct PresentationSessionMessage;
 class RenderFrameHost;
 
 // Implementation of Mojo PresentationService.
@@ -267,6 +268,13 @@ class CONTENT_EXPORT PresentationServiceImpl
       const std::string& presentation_id,
       const NewSessionMojoCallback& callback);
 
+  // Passed to embedder's implementation of PresentationServiceDelegate for
+  // later invocation when session messages arrive.
+  // For optimization purposes, this method will empty the messages
+  // passed to it.
+  void OnSessionMessages(
+      scoped_ptr<ScopedVector<PresentationSessionMessage>> messages);
+
   // Removes the head of the queue (which represents the request that has just
   // been processed).
   // Checks if there are any queued StartSession requests and if so, executes
@@ -318,6 +326,8 @@ class CONTENT_EXPORT PresentationServiceImpl
   // The binding is removed when binding_ is cleared or goes out of scope.
   scoped_ptr<mojo::Binding<presentation::PresentationService>> binding_;
 
+  scoped_ptr<SessionMessagesCallback> on_session_messages_callback_;
+
   // ID of the RenderFrameHost this object is associated with.
   int render_process_id_;
   int render_frame_id_;