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..b78f1e3a5079262b7a8efe286f7f712830b8f5f3 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);
 
+  void OnSessionMessages(
+      const SessionMessagesCallback& callback,
+      scoped_ptr<ScopedVector<PresentationSessionMessage>> messages);
+
+  static presentation::SessionMessagePtr ToMojoSessionMessage(
+      content::PresentationSessionMessage* input);
+
   // 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