Triggering a hot restart with no changes causes a blank page

[grouma]

Steps to reproduce:

1. Run the basic hello world app with --debug (don't provide the --auto flag)
2. Open the devtools
3. Click hot restart
4. Notice the application goes blank

[devoncarew]

I see something like this from IntelliJ; generally, the first restart doesn't show content in the target chrome process, but the 2nd restart will. I.e., after making changes to the app, I have to restart twice to see those changes in the browser.

[jakemac53]

I can't repro this on hello_world but I can repro it for flutter. Looks like at least one part of it is a pretty easy fix.

[devoncarew]

Verified that this is working for IntelliJ now.