Track ascii-ness of data in externalized strings.

src/flag-definitions.h

 // Copyright 2008 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 105 matching lines @@
             "enable use of SAHF instruction if available (X64 only)")
 DEFINE_bool(enable_vfp3, true,
             "enable use of VFP3 instructions if available (ARM only)")
 DEFINE_bool(enable_armv7, true,
             "enable use of ARMv7 instructions if available (ARM only)")
 
 // bootstrapper.cc
 DEFINE_string(expose_natives_as, NULL, "expose natives in global object")
 DEFINE_string(expose_debug_as, NULL, "expose debug in global object")
 DEFINE_bool(expose_gc, false, "expose gc extension")
+DEFINE_bool(expose_externalize_string, false,
+            "expose externalize string extension")
 DEFINE_int(stack_trace_limit, 10, "number of stack frames to capture")
 DEFINE_bool(disable_native_files, false, "disable builtin natives files")
 
 // builtins-ia32.cc
 DEFINE_bool(inline_new, true, "use fast inline allocation")
 
 // checks.cc
 DEFINE_bool(stack_trace_on_abort, true,
             "print a stack trace if an assertion failure occurs")
 
@@ skipping 306 matching lines @@
 #undef FLAG
 
 #undef DEFINE_bool
 #undef DEFINE_int
 #undef DEFINE_string
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META