Revert of [Presentation API / Media Router] Clean up default pres URL logic.

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 54e1a4c14975d0589cf37ae56169a4c07ce7ead5..220c256a5dc7ff31bd51271ffa98fad6ae679c34 100644
--- a/content/browser/presentation/presentation_service_impl.h
+++ b/content/browser/presentation/presentation_service_impl.h
@@ -94,7 +94,7 @@
   // Maximum number of pending JoinSession requests at any given time.
   static const int kMaxNumQueuedSessionRequests = 10;
 
-  using PresentationSessionMojoCallback =
+  using DefaultSessionMojoCallback =
       mojo::Callback<void(presentation::PresentationSessionInfoPtr)>;
   using SessionStateCallback =
       mojo::Callback<void(presentation::PresentationSessionInfoPtr,
@@ -125,6 +125,27 @@
     PresentationServiceImpl* const service_;
   };
 
+  class CONTENT_EXPORT DefaultSessionStartContext {
+   public:
+    DefaultSessionStartContext();
+    ~DefaultSessionStartContext();
+
+    // Adds a callback. May invoke the callback immediately if |session| using
+    // default presentation URL was already started.
+    void AddCallback(const DefaultSessionMojoCallback& callback);
+
+    // Sets the session info. Maybe invoke callbacks queued with AddCallback().
+    void set_session(const PresentationSessionInfo& session);
+
+   private:
+    // Flush all queued callbacks by invoking them with null
+    // PresentationSessionInfoPtr.
+    void Reset();
+
+    ScopedVector<DefaultSessionMojoCallback> callbacks_;
+    scoped_ptr<PresentationSessionInfo> session_;
+  };
+
   // Ensures the provided NewSessionMojoCallback is invoked exactly once
   // before it goes out of scope.
   class NewSessionMojoCallbackWrapper {
@@ -156,6 +177,8 @@
   void SetClient(presentation::PresentationServiceClientPtr client) override;
   void ListenForScreenAvailability(const mojo::String& url) override;
   void StopListeningForScreenAvailability(const mojo::String& url) override;
+  void ListenForDefaultSessionStart(
+      const DefaultSessionMojoCallback& callback) override;
   void StartSession(
       const mojo::String& presentation_url,
       const NewSessionMojoCallback& callback) override;
@@ -185,11 +208,8 @@
 
   // PresentationServiceDelegate::Observer
   void OnDelegateDestroyed() override;
-
-  // Passed to embedder's implementation of PresentationServiceDelegate for
-  // later invocation when default presentation has started.
-  void OnDefaultPresentationStarted(
-      const PresentationSessionInfo& session_info);
+  void OnDefaultPresentationStarted(const PresentationSessionInfo& session)
+      override;
 
   // Finds the callback from |pending_join_session_cbs_| using
   // |request_session_id|.
@@ -264,6 +284,8 @@
   base::hash_map<int, linked_ptr<NewSessionMojoCallbackWrapper>>
       pending_join_session_cbs_;
 
+  scoped_ptr<DefaultSessionStartContext> default_session_start_context_;
+
   // RAII binding of |this| to an Presentation interface request.
   // The binding is removed when binding_ is cleared or goes out of scope.
   scoped_ptr<mojo::Binding<presentation::PresentationService>> binding_;