Implementing closeSession from WebPresentationClient to PresentationService.

content/renderer/presentation/presentation_dispatcher.h

Index: content/renderer/presentation/presentation_dispatcher.h
diff --git a/content/renderer/presentation/presentation_dispatcher.h b/content/renderer/presentation/presentation_dispatcher.h
index e17d72ac0e6e24ac3ff340c2e841cab03c366860..debd9f94f8b9d36d9fa5e46e4c10c8fac3c24692 100644
--- a/content/renderer/presentation/presentation_dispatcher.h
+++ b/content/renderer/presentation/presentation_dispatcher.h
@@ -41,6 +41,9 @@ class CONTENT_EXPORT PresentationDispatcher
       const blink::WebString& presentationUrl,
       const blink::WebString& presentationId,
       blink::WebPresentationSessionClientCallbacks* callback);
+  virtual void closeSession(
+      const blink::WebString& presentationUrl,
+      const blink::WebString& presentationId);
 
   // RenderFrameObserver
   void DidChangeDefaultPresentation() override;