Evaluate newly introduced "Close Saved" Activity icon context menu item

[per1234]

Describe the current behavior

The user interface of the Arduino IDE is carefully designed to provide a gentle learning curve and a distraction-free environment. For this reason, only a curated subset of the general purpose capabilities of the Eclipse Theia IDE framework are exposed via the primary UI.

Theia provides the ability to remove icons from the "Activity Bar". Some target users of complex Theia-based applications may have large numbers of icons on the bar or prefer to use the "Command Palette" exclusively, and so find the ability to remove them useful.

A "Close Saved" option which causes the loss of the "Activity Bar" icons was added to the primary UI of the Arduino IDE. The Arduino IDE's activity bar only contains four icons. The "Command Palette" is not intended as part of the primary UI. For this reason, the users don't have a need to remove the "Activity Bar" and may be concerned if they inadvertently do so via the cryptically titled context menu item.

To reproduce

1. Right click on any of the icons on the "Activity Bar"
   
2. Select "Close Saved" from the context menu:
   🙁 The "Activity Bar" disappears:
   
3. Select File > Quit from the Arduino IDE menus.
4. Start the Arduino IDE.
   🙁 The "Activity Bar" has only been partially restored:
   

Describe the request

I suspect this option may have been introduced unintentionally. If so, it should be evaluated to determine whether it is of value or should be removed.

Desktop

• OS: Windows 10
• Version: 2.0.0-rc3-snapshot-2f9bf86
  Date: 2022-02-11T14:52:06.341Z
  CLI Version: 0.21.0 [10107d24]

Additional context

I bisected the change to 112153f (it does not exist in the build from the previous commit 69ac1f4).

[per1234]

Fixed by #940