Introduce a kill-switch for shipping features.

src/mksnapshot.cc

 // Copyright 2006-2008 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.
 
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
 
 #include "src/v8.h"
 
@@ skipping 244 matching lines @@
     fprintf(stderr, "%c", i < message->GetStartColumn() ? ' ' : '^');
   }
   fprintf(stderr, "\n");
 }
 
 
 int main(int argc, char** argv) {
   // By default, log code create information in the snapshot.
   i::FLAG_log_code = true;
 
+  // Omit from the snapshot natives for features that can be turned off
+  // at runtime.
+  i::FLAG_harmony_shipping = false;
+
   // Print the usage if an error occurs when parsing the command line
   // flags or if the help flag is set.
   int result = i::FlagList::SetFlagsFromCommandLine(&argc, argv, true);
   if (result > 0 || argc != 2 || i::FLAG_help) {
     ::printf("Usage: %s [flag] ... outfile\n", argv[0]);
     i::FlagList::PrintHelp();
     return !i::FLAG_help;
   }
 
   i::CpuFeatures::Probe(true);
@@ skipping 99 matching lines @@
                            context_ser);
     }
   }
 
   isolate->Dispose();
   V8::Dispose();
   V8::ShutdownPlatform();
   delete platform;
   return 0;
 }