[Interpreter] Refactor bytecode generator test suite.

test/cctest/cctest.isolate

 # Copyright 2015 the V8 project 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': [
       './cctest.status',
       './testcfg.py',
+      './interpreter/bytecode_expectations/',
     ],
   },
   'includes': [
     'cctest_exe.isolate',
     '../../tools/testrunner/testrunner.isolate',
   ],
 }