Keep scroll position stable when closing a tab in the tab well

[PunchyRascal]

• VSCode Version: Code 1.5.3 (5be4091, 2016-09-22T08:50:42.185Z)
• OS Version: Windows_NT ia32 10.0.14393

Steps to Reproduce:

1. open many files so that tabs are scrollable, have the first (left-most) tab active
2. scroll to the farthest (right-most) tabs
3. close a tab in that area
4. the whole tab bar scrolls back to the left-most position (active tab)

This leads to loss of focus and confusion. If I want to close multiple tabs there, I have to scroll to them each time I close one.

[bpasero]

@PunchyRascal share a video? I think this behaviour is intentional if the first tab was active before opening the last one (we go back in MRU order and open it).

[PunchyRascal]

I see no reason to generate focus to active tab since the tab never lost the focus, it is still open, I am just trying to close a few tabs at the end of the tab bar, I am not activating other tabs or closing active tab.

I edited the initial report for better clarity.

[bpasero]

@PunchyRascal oh yeah I see it, uncooool

[bpasero]

I am undecided how to best fix this because it might also cause in users reporting issues why the current tab is not revealed. I think eventually maybe it needs to boil down to a setting which sucks too.

Maybe a delay could be added that after a close we only reveal the active tab after some timeout so that you can continue closing tabs without loosing context.

Anyway, I would accept a PR in this area if someone wants to jump in 👍