Memory panel has confusing banner in offline mode

Steps to reproduce:

1. Open the memory panel when devtools is in offline mode
2. At the top, there is a banner about http traffic being logged

I would expect this banner not to be there since there is no connected app

Start by reproducing the issue in the DevTools memory panel with offline mode enabled, then inspect the memory panel's HTTP-traffic banner entry point. Done means the banner is absent when no app is connected while the panel remains usable; verify the behavior in both offline and connected modes.

索引モデルが issue の本文から書いたものです。