Switch to Unsaved Tab When Prompting to Save

[jonatino]

• VSCode Version: 1.9.0-insiders
• OS Version: Windows 10 x64 Pro

Steps to Reproduce:

1. Open any file in VSCode (We will call this tab A)
2. Create new untitled tab and make changes but do not save (We will call this tab B)
3. Switch back to tab A
4. Right click tab A select close others

I think the 'Do you want to save the changes you made to Untitled-1?' should switch to the appropriate tab (in this case tab B) to show the user the contents before they decide to delete them forever.

[jonatino]

I will take a stab at this :)

[jontro]

In addition to this it would be great if all saved files will be closed automatically even if you press cancel