Add a parameter for ContentDialog.ShowAsync() to specify the target window

[TSRBerry]

We are currently running into Linux specific issues with ContentDialog at Ryujinx, because for some reason our overlay window still has IsActive == false when ShowAsync() is called. On Windows it works fine, but on Linux we couldn't find a way to force IsActive == true even tho we were able to make sure it's true before we call ShowAsync().

This is why I created this method. Using this method we get consistent behavior across all platforms and don't need to worry about IsActive. Usually we would just use a subclass of ContentDialog for this, but since it accesses a lot of private variables, this wasn't really easy to do.

I bet this method also has other usecases, but I figured it might be best to explain why this was needed in the first place.

[TSRBerry]

How does that look?

[amwx]

Minor nit, otherwise looks good, thanks!

Also, I'll do a formal deprecation/removal of ContentDialogPlacement later in a separate PR so I won't worry here about preserving the optional parameter.

[TSRBerry]

Could we also backport this to 1.4.4? So we could use this feature with our current version?
If you are okay with that should I create another PR or would this be handled differently?

[amwx]

Could we also backport this to 1.4.4? So we could use this feature with our current version? If you are okay with that should I create another PR or would this be handled differently?

This *should* be possible since its a fairly straight-forward change - but master's source is v2/11.0 so I can't just cherry-pick the commit. I'll see what I can do sometime this week.

[TSRBerry]

I thought the code for 1.4.4 for ContentDialog is the same as for master right now, so cherry-picking that commit should work, but if it's different and I'm misremembering then I'm not sure what the best approach would be.

Thank you for helping us! :D

[amwx]

I thought the code for 1.4.4 for ContentDialog is the same as for master right now, so cherry-picking that commit should work, but if it's different and I'm misremembering then I'm not sure what the best approach would be.

Thank you for helping us! :D

#242 is the most recent change to ContentDialog which are v2 fixes only (theres a couple breaking changes and new APIs that rely on stuff added only in the v2 stuff), and there were a couple changes within ShowAsync that would've conflicted. I'm pretty much full steam ahead on v2/11.0 now, and because there's so many big changes on going most stuff won't be backported unless its a critical bug fix.
Anyway, I've pushed 1.4.5 package with this fix in it so hopefully that helps

[TSRBerry]

Thank you very much!