Disable string externalization by default.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "lib/stacktrace.h"
@@ skipping 41 matching lines @@
 
 
 DECLARE_FLAG(bool, print_class_table);
 DECLARE_FLAG(bool, verify_handles);
 #if defined(DART_NO_SNAPSHOT)
 DEFINE_FLAG(bool, check_function_fingerprints, true,
             "Check function fingerprints");
 #endif  // defined(DART_NO_SNAPSHOT).
 DEFINE_FLAG(bool, verify_acquired_data, false,
             "Verify correct API acquire/release of typed data.");
-DEFINE_FLAG(bool, support_externalizable_strings, true,
+DEFINE_FLAG(bool, support_externalizable_strings, false,
             "Support Dart_MakeExternalString.");
 
 
 ThreadLocalKey Api::api_native_key_ = kUnsetThreadLocalKey;
 Dart_Handle Api::true_handle_ = NULL;
 Dart_Handle Api::false_handle_ = NULL;
 Dart_Handle Api::null_handle_ = NULL;
 Dart_Handle Api::empty_string_handle_ = NULL;
 
 
@@ skipping 6047 matching lines @@
   return Api::Success();
 }
 #endif  // DART_PRECOMPILER
 
 
 DART_EXPORT bool Dart_IsRunningPrecompiledCode() {
   return Dart::IsRunningPrecompiledCode();
 }
 
 }  // namespace dart