Apply revealInExplorer vscode command

[vinokurig]

What it does

Apply revealInExplorer built-in vscode command. It is used in the built-in vscode git extension: https://github.com/microsoft/vscode/blob/a5987ce853b0cd757f140f4618962a4e12522224/extensions/git/src/commands.ts#L2232.

How to test

1. Remove "@theia/git": "^1.5.0" from examples/browser/package.json file.
2. Download vscode-git-1.44.2 and copy it to the plugins folder.
3. Compile and start theia with a project cloned from github.
4. Make some changes in the project.
5. Open the Source Control panel and right mouse click to a changed item => Reveal in Side Bar
   See: the item is selected in the Navigator:
   

Review checklist

• as an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• as a reviewer, I agree to behave in accordance with the review guidelines

[azatsarynnyy]

Works as described 👍

[vinokurig]

@akosyakov @westbury is it OK for you to merge?

[vince-fugnitto]

@vinokurig the reveal in explorer works well except for the case that the explorer does not exist in the layout. A similar scenario in vscode will open the explorer and reveal.

[azatsarynnyy]

@vinokurig Anton is offline this week

[vinokurig]

@vince-fugnitto

@vinokurig the reveal in explorer works well except for the case that the explorer does not exist in the layout. A similar scenario in vscode will open the explorer and reveal.

Added open the file navigator if it closed. Could you please review it again?

[vince-fugnitto]

The changes look good to me 👍
I verified that:

• the command reveals the proper resource in the explorer
• the command toggles the explorer first if it is does not exist before revealing
• performing a multi-selection reveal behaves similarly to vscode

[vince-fugnitto]

@vinokurig would you like to merge for today's release?

[vinokurig]

@vince-fugnitto Yes, I'll merge it when CI tests are passed.