Portal sometimes undecorated

[danirabbit]

What Happened?

It seems like there's some kind of race where the portal starts up before Gala sometimes and we end up with undecorated windows:

Steps to Reproduce

1. Start a new session
2. Do something that triggers the request portal
3. Notice that it's not decorated

Expected Behavior

We should make sure to wait until the window manager is started before starting portals so that we get decorated windows

OS Version

7.x (Horus)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

No response