Fix sbox_validation_tests & Make isolate_driver.py include the executable itself

courgette/courgette_unittests.isolate

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 {
   'variables': {
     'files': [
-      '<(PRODUCT_DIR)/courgette_unittests<(EXECUTABLE_SUFFIX)',
       'testdata/',
     ],
     'command': [
       '<(PRODUCT_DIR)/courgette_unittests<(EXECUTABLE_SUFFIX)',
     ],
   },
   # Need the shared runtime libs on Windows.
   'includes': [
     '../base/base.isolate',
   ],
 }