custom-editor: update opener to respect option

[vince-fugnitto]

What it does

The pull-request updates the custom-editor to properly respect the option priority which is used to control the opener behavior.
The option priority is used by custom-editors to declare that they do not want to open with the custom-editor by default but instead with the regular opener (editor). Previously, despite option being set, the custom-editor would always be opened as it incorrectly had a higher priority than other openers.

How to test

• include the following test plugin to your application vscode-custom-editor
• start the application and use exampleFiles as a workspace
• confirm that pawDraw opens with a custom-editor
• confirm that cscratch opens with the regular editor
• confirm that cscratch can use open with... to open with the custom-editor

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

Signed-off-by: vince-fugnitto [email protected]

[msujew]

LGTM. I can confirm that the issue exists on master and is addressed by these changes nicely.

FYI, the pawDraw webview doesn't seem to work correctly as I get an error:

TypeError: vscode.workspace.fs.isWritableFileSystem is not a function

But that's unrelated to the changes.

[vince-fugnitto]

TypeError: vscode.workspace.fs.isWritableFileSystem is not a function

@msujew 👍 I think we should write an issue to track it if not already done, I do see that #9863 mentions it is not implemented yet.