Focus editor for tab after dragged over for 1500 millis

[MachineMitch21]

This PR implements #148664

This PR fulfills the requirements, but I think it could be better.
Perhaps we need a setting to indicate if this feature should be active
and also how long the delay should be before we focus the other editor?

[bpasero]

I pushed a small 💄 and think the code is generally OK to ship like this but I do agree:

• do we need a setting?
• what should be the default timeout to open the editor?

Some pointers:

• macOS has an accessibility feature called "Spring loading delay" (System Preferences, Accessibility, Pointer Control) that enables/disables this for the macOS dock and allows to adjust the delay with a slider
• our very own activity bar has a hardcoded delay of 800ms to open the view that is dragged over via DelayedDragHandler

My first thought was to align activity bar and tabs to be 800ms, but then I feel maybe users are getting frustrated that the active editor changes so quickly when you drag and drop over tabs?

@mjbvz thoughts on this?

Maybe also @daviddossett ?

[daviddossett]

I think 800 is fine. Comparing the two..

800ms

800ms.mp4

1500ms

1500ms.mp4

It might make sense to consider this a setting that applies to these situations globally at some point so users can tune it. Kind of like the macOS example @bpasero mentioned. Rather than having a specific setting for each one, that is.

[bpasero]

Let's just ship this in insiders and wait for feedback with 1500ms, then we can tweak according to real user feedback.