[PresentationAPI] Plumbing |onstatechange| event for the PresentationSession from Blink to platform/

public/platform/modules/presentation/WebPresentationSessionClient.h

Index: public/platform/modules/presentation/WebPresentationSessionClient.h
diff --git a/public/platform/modules/presentation/WebPresentationSessionClient.h b/public/platform/modules/presentation/WebPresentationSessionClient.h
index 735ff3cd1602ac6c935cd078eb372a9b416930d3..641482049abb1e5e4878a675cf61129445450fe4 100644
--- a/public/platform/modules/presentation/WebPresentationSessionClient.h
+++ b/public/platform/modules/presentation/WebPresentationSessionClient.h
@@ -12,6 +12,13 @@ namespace blink {
 // The implementation the embedder has to provide for the Presentation API to work.
 class WebPresentationSessionClient {
 public:
+    enum SessionState {

[mlamouri (slow - plz ping), 2015/03/23 17:54:16]

Could you make this an enum class?

It will require you to rename SessionStafeValue as Value but it will allow
forward declaration.

[whywhat, 2015/03/23 21:12:16]

Done.

+        SessionStateConnected = 0,
+        SessionStateDisconnected,
+        SessionStateUnknown,

[Peter Beverloo, 2015/03/20 19:07:40]

When would we use "Unknown"?

[whywhat, 2015/03/23 21:12:16]

When WFT happens?

+        SessionStateLast = SessionStateUnknown

[mlamouri (slow - plz ping), 2015/03/23 17:54:16]

Do you use SessionStateLast? It is commonly used for IPC but I assume you will
be using Mojo, right?

[whywhat, 2015/03/23 21:12:17]

No, I have it for consistency only.

+    };
+
     virtual ~WebPresentationSessionClient() { }
 
     virtual WebString getId() = 0;