[Media Router] Use origin instead of URL for frame.

chrome/browser/media/router/presentation_request.h

Index: chrome/browser/media/router/presentation_request.h
diff --git a/chrome/browser/media/router/presentation_request.h b/chrome/browser/media/router/presentation_request.h
index 9a3009a52b26163aa0678b0856b48ea27c2b5a71..56265c9acaea4b198c48950db0c63974e9370654 100644
--- a/chrome/browser/media/router/presentation_request.h
+++ b/chrome/browser/media/router/presentation_request.h
@@ -44,6 +44,8 @@ class PresentationRequest {
   const std::vector<GURL> presentation_urls_;
 
   // URL of frame from which the request was initiated.
+  // TODO(crbug.com/632623): Convert this to url::Origin as only the origin or
+  // hostname is used.
   const GURL frame_url_;
 };