Move recipe engine to third_party/recipe_engine.

scripts/slave/isolation/recipes.isolate

 # Copyright 2014 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.
 #
 # This permits isolating the recipes so they can be run from a Swarming bot (or
 # anywhere, really).
 #
 # This file MUST be 4 directories down the root directory. It cannot be in
 # scripts/slave/. See recipe_modules/path/config.py.
 #
 # Expected trigger additional arguments:
 #   '--build-properties={...}' '--factory-properties={...}'
 #
 {
   'variables': {
     'command': [
       'python', '../../tools/runit.py', '--show-path', '../annotated_run.py',
     ],
     'files': [
       '../../../../depot_tools/',
       '../../../environment.cfg.py',
       '../../../site_config/',
       '../../../goma/',
       '../../../third_party/infra/',
       '../../../third_party/mock-1.0.1/',
+      '../../../third_party/recipe_engine/',
       '../../common/',
       '../../tools/runit.py',
       '../__init__.py',
-      '../annotated_run.py',
       '../annotation_utils.py',
       '../bootstrap.py',
       '../bot_update.py',
       '../build_directory.py',
       '../cleanup_temp.py',
       '../compile.py',
       '../crash_utils.py',
-      '../field_composer.py',
       '../gsutil',
       '../gsutil.bat',
       '../gtest/',
       '../gtest_slave_utils.py',
       '../performance_log_processor.py',
-      '../recipe_api.py',
-      '../recipe_config.py',
-      '../recipe_config_types.py',
-      '../recipe_loader.py',
       '../recipe_modules/',
-      '../recipe_test_api.py',
-      '../recipe_util.py',
       '../recipes/',
       '../results_dashboard.py',
       '../runtest.py',
       '../runisolatedtest.py',
       '../skia/',
       '../slave_utils.py',
       '../telemetry_utils.py',
       '../xvfb.py',
     ],
   },
 }