[CrOS MultiDevice] Fix comment in PendingConnectionRequestDelegate.

Previously, it referenced PendingConnectionRequest::GetRequestId(), but
the function is actually named PendingConnectionRequest::request_id().

Bug: 824568, 752273
Change-Id: I60fcd2dfe5863e6361c9820f1a2720c30f36be1a
Reviewed-on: https://chromium-review.googlesource.com/1058435
Commit-Queue: Ryan Hansberry <hansberry@chromium.org>
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558512}

chromeos/services/secure_channel/pending_connection_request_delegate.h

@@ -30,7 +30,7 @@ class PendingConnectionRequestDelegate {
 
   // Invoked when a PendingConnectionRequest fails to establish a connection.
   // |request_id| corresponds to the ID returned by
-  // PendingConnectionRequest::GetRequestId().
+  // PendingConnectionRequest::request_id().
   virtual void OnRequestFinishedWithoutConnection(
       const std::string& request_id,
       FailedConnectionReason reason) = 0;