Added plumbing for the availablechange event from Blink to WebPresentationClient.

public/web/WebFrameClient.h

Index: public/web/WebFrameClient.h
diff --git a/public/web/WebFrameClient.h b/public/web/WebFrameClient.h
index 62641d2a76f6e397b5b148989bc3f621fb8c0ce5..29f3eddea61188120fadafb58aa4e8c36ff0dc0f 100644
--- a/public/web/WebFrameClient.h
+++ b/public/web/WebFrameClient.h
@@ -75,6 +75,7 @@ class WebServiceWorkerProvider;
 class WebSocketHandle;
 class WebPlugin;
 class WebPluginPlaceholder;
+class WebPresentationClient;
 class WebPushClient;
 class WebRTCPeerConnectionHandler;
 class WebScreenOrientationClient;
@@ -333,6 +334,11 @@ public:
     virtual WebPushClient* pushClient() { return 0; }
 
 
+    // Presentation API ----------------------------------------------------
+
+    // Used to access the embedder for the Presentation API
+    virtual WebPresentationClient* presentationClient() { return 0; }

[Peter Beverloo, 2015/01/07 14:29:09]

nit: two blank lines under here for consistency. End the comment sentence with a
period.

[whywhat, 2015/01/07 16:22:16]

Done.

+
     // Editing -------------------------------------------------------------
 
     // These methods allow the client to intercept and overrule editing