Gets presentation ID from route ID upon route creation, and overrides previous presentation ID with…

chrome/browser/media/router/media_route.h

Index: chrome/browser/media/router/media_route.h
diff --git a/chrome/browser/media/router/media_route.h b/chrome/browser/media/router/media_route.h
index e8d270ae7dba683e6ff9880ac0f363c1320ed57f..8e47ee36db31ec77fe5ff50a4789802c9b776298 100644
--- a/chrome/browser/media/router/media_route.h
+++ b/chrome/browser/media/router/media_route.h
@@ -79,6 +79,11 @@ class MediaRoute {
   MediaRouteState state_;
 };
 
+// Return a pair of Presentation ID and URL. If the input route ID is invalid,
+// a pair of empty strings is returned.
+std::pair<std::string, std::string> GetPresentationIdAndUrl(
+    const MediaRoute::Id& id);
+
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTE_H_