src/vs/workbench/contrib/bulkEdit/browser/preview/bulkEditTree.ts/TextEditElement/setChecked
class TextEditElement:	setChecked(value: boolean): void {
		let model = this.parent.parent;
		if (model instanceof CategoryElement) {
			model = model.parent;
		}

		// check/uncheck this element
		model.checked.updateChecked(this.edit.textEdit, value);

		// make sure parent is checked when this element is checked...
		if (value) {
			for (const edit of this.parent.edit.originalEdits.values()) {
				if (edit instanceof ResourceFileEdit) {
					(<BulkFileOperations>model).checked.updateChecked(edit, value);
				}
			}
		}
	}