Could not auto close unsaved editor when delete

The newly added "delete" feature #343 works well when we try to delete unchanged files. However, if we try to delete file with unsaved changes, the editor will not be closed and will looks like below:

This is not consistent with native file explorer's behavior and may also cause user lose their changes before deletion. However, this part is hard to fix due to API limitation, since many needed functions are encapsulated within the implementation of VS Code built-in commands. If microsoft/vscode#107566 could be solved, we can fix this problem easily.

Comienza con la funcionalidad de eliminación del issue #343 y reproduce la eliminación de un archivo con cambios sin guardar en la extensión de VS Code. Lee microsoft/vscode#107566 para entender la limitación de la API; se considera terminado cuando el editor se cierra de forma coherente con el comportamiento nativo del explorador de archivos, sin poner en riesgo los cambios sin guardar.