Fix restoration of problems (from watch task) when closing a file

[russelldavis]

Fixes #47386

Logic was added in df97bc3 to add a watcher's problems back to the problems view after closing a file.

It doesn't work quite right though because of how processLineInternal batches up changes, only sending them to markerService when it gets called on subsequent lines with a different owner or resource.

Because of that, the current behavior is that when you close a file with errors, the errors will disappear and only end up getting restored the next time a different file being watched gets saved.

This PR fixes that (restoring the errors right after the file is closed) by calling forceDelivery().

cc @alexr00

[russelldavis]

Welp, I'm pretty sure my explanation above is wrong, and thus this PR is also the wrong fix. There is indeed a problem with restoring the problems when closing a file, but it looks like the actual cause is a race condition between the debounce timeout at

vscode/src/vs/workbench/contrib/tasks/common/problemCollectors.ts

Lines 437 to 439 in 91070de

	Event.debounce(this.markerService.onMarkerChanged, (last: readonly URI[] | undefined, e: readonly URI[]) => {
	return (last ?? []).concat(e);
	}, 500)(async (markerEvent) => {

and the cleanup timeout at

vscode/src/vs/workbench/contrib/tasks/common/problemCollectors.ts

Lines 450 to 453 in 91070de

	setTimeout(async () => {
	markerChanged?.dispose();
	markerChanged = undefined;
	}, 600);

Sorry for the confusion. Will follow up later with a proper fix.

[russelldavis]

The proper fix for this is now at #183271