Introduce a kill-switch for shipping features.

src/flag-definitions.h

 // Copyright 2012 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.
 
 // This file defines all of the flags.  It is separated into different section,
 // for Debug, Release, Logging and Profiling, etc.  To add a new flag, find the
 // correct section, and use one of the DEFINE_ macros, without a trailing ';'.
 //
 // This include does not have a guard, because it is a template-style include,
 // which can be included multiple times in different modes.  It expects to have
@@ skipping 139 matching lines @@
 //
 // Flags in all modes.
 //
 #define FLAG FLAG_FULL
 
 // Flags for language modes and experimental language features.
 DEFINE_BOOL(use_strict, false, "enforce strict mode")
 
 DEFINE_BOOL(es_staging, false, "enable all completed harmony features")
 DEFINE_BOOL(harmony, false, "enable all completed harmony features")
+DEFINE_BOOL(harmony_shipping, true, "enable all shipped harmony fetaures")
 DEFINE_IMPLICATION(harmony, es_staging)
 DEFINE_IMPLICATION(es_staging, harmony)
 
 // Features that are still work in progress (behind individual flags).
 #define HARMONY_INPROGRESS(V)                                     \
   V(harmony_modules, "harmony modules (implies block scoping)")   \
   V(harmony_arrays, "harmony array methods")                      \
   V(harmony_classes,                                              \
     "harmony classes (implies block scoping & object literal extension)") \
   V(harmony_object_literals, "harmony object literal extensions") \
@@ skipping 23 matching lines @@
   DEFINE_BOOL(id, false, "enable " #description " (in progress)")
 HARMONY_INPROGRESS(FLAG_INPROGRESS_FEATURES)
 #undef FLAG_INPROGRESS_FEATURES
 
 #define FLAG_STAGED_FEATURES(id, description) \
   DEFINE_BOOL(id, false, "enable " #description) \
   DEFINE_IMPLICATION(es_staging, id)
 HARMONY_STAGED(FLAG_STAGED_FEATURES)
 #undef FLAG_STAGED_FEATURES
 
-#define FLAG_SHIPPING_FEATURES(id, description) \
-  DEFINE_BOOL_READONLY(id, true, "enable " #description)
+#define FLAG_SHIPPING_FEATURES(id, description)  \
+  DEFINE_BOOL(id, false, "enable " #description) \
+  DEFINE_IMPLICATION(harmony_shipping, id)
 HARMONY_SHIPPING(FLAG_SHIPPING_FEATURES)
 #undef FLAG_SHIPPING_FEATURES
 
 
 // Feature dependencies.
 DEFINE_IMPLICATION(harmony_modules, harmony_scoping)
 DEFINE_IMPLICATION(harmony_classes, harmony_scoping)
 DEFINE_IMPLICATION(harmony_classes, harmony_object_literals)
 
 
@@ skipping 774 matching lines @@
 #undef DEFINE_ALIAS_FLOAT
 #undef DEFINE_ALIAS_ARGS
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META
 #undef FLAG_MODE_DEFINE_IMPLICATIONS
 
 #undef COMMA