src/vs/editor/contrib/folding/folding.ts/FoldAllBlockCommentsAction/invoke
class FoldAllBlockCommentsAction:	invoke(_foldingController: FoldingController, foldingModel: FoldingModel, editor: ICodeEditor): void {
		if (foldingModel.regions.hasTypes()) {
			setCollapseStateForType(foldingModel, FoldingRangeKind.Comment.value, true);
		} else {
			const editorModel = editor.getModel();
			if (!editorModel) {
				return;
			}
			let comments = LanguageConfigurationRegistry.getComments(editorModel.getLanguageIdentifier().id);
			if (comments && comments.blockCommentStartToken) {
				let regExp = new RegExp('^\\s*' + escapeRegExpCharacters(comments.blockCommentStartToken));
				setCollapseStateForMatchingLines(foldingModel, regExp, true);
			}
		}
	}