Save UI state periodically to prevent loss on shutdown

[jankalfus]

• VSCode Version: 1.5.2
• OS Version: Windows 10

Steps to Reproduce:

1. Let VS Code open, lock the computer
2. Let Windows install updates and automatically restart the computer

After logging into Windows and launching VS Code, VS Code opens the project that was opened last time, but it doesn't restore editors to the state they were in last time. It restores some much older state instead (probably from last time the "Close folder" menu option was used). Very annoying.

[bpasero]

@jankalfus this indicates that Windows is not shutting down VS Code gracefully but rather terminates it. We would need to periodically save UI state to prevent that.

[jankalfus]

I have also noticed that when using F12 (Go to Definition), VS Code can be confused with certain files (probably those that weren't existing in the restored state, but were created later).

The issue is the following (BTW this relates to TypeScript .tsx and .ts files, I haven't tested any others):
When using F12 with a symbol, VS Code opens a new editor tab with an identical file opened and sets the cursor at the import, instead of going to the symbol import in the currenty opened editor tab. Expected behavior is to just set the cursor in the currently opened tab.

[YoshiWalsh]

I'm not sure that periodically saving the UI state is the only way to achieve this. With other Windows programs, they appear to be able to execute some code when the computer shuts down. For instance, Paint.NET will prompt you to save any unsaved changes, and will even halt the shutdown until you have given a response.

I'm having trouble finding up-to-date documentation about this, but it seems in Vista Windows was changed to allow programs 2 seconds to exit once a shutdown is initiated (https://blogs.msdn.microsoft.com/oldnewthing/20070416-00/?p=27243/), and I can't see any sign that this has been changed since. Would it be possible to use this time to store the UI state?