[compiler] Make --debug-code the default in debug builds.

tools/run-tests.py

 #!/usr/bin/env python
 #
 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 109 matching lines @@
   # The default for developer workstations.
   "dev": VARIANTS,
   # Additional variants, run on all bots.
   "more": MORE_VARIANTS,
   # Additional variants, run on a subset of bots.
   "extra": ["nocrankshaft"],
 }
 
 DEBUG_FLAGS = ["--nohard-abort", "--nodead-code-elimination",
                "--nofold-constants", "--enable-slow-asserts",
-               "--debug-code", "--verify-heap"]
+               "--verify-heap"]
 RELEASE_FLAGS = ["--nohard-abort", "--nodead-code-elimination",
                  "--nofold-constants"]
 
 MODES = {
   "debug": {
     "flags": DEBUG_FLAGS,
     "timeout_scalefactor": 4,
     "status_mode": "debug",
     "execution_mode": "debug",
     "output_folder": "debug",
@@ skipping 779 matching lines @@
         "--coverage-dir=%s" % options.sancov_dir])
     except:
       print >> sys.stderr, "Error: Merging sancov files failed."
       exit_code = 1
 
   return exit_code
 
 
 if __name__ == "__main__":
   sys.exit(Main())