am 7a9cda18: Merge "Defend against missing DB during migration." into jb-ub-now-kermit

    public void deleteDatabase() {

        // Are you sure? (y/n)

        final SQLiteDatabase db = mOpenHelper.getWritableDatabase();

        final String dbFile = db.getPath();

        final File dbFile = new File(db.getPath());

        mOpenHelper.close();

        SQLiteDatabase.deleteDatabase(new File(dbFile));

        if (dbFile.exists()) {

            SQLiteDatabase.deleteDatabase(dbFile);

        }

        mOpenHelper = new DatabaseHelper(getContext());

    }