Add some support for the code-point code-unit distinction.

runtime/vm/debugger.cc

 // Copyright (c) 2012, 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 "vm/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 1212 matching lines @@
   Class& cls = Class::Handle(isolate_);
   String& field_name = String::Handle(isolate_);
   Object& field_value = Object::Handle(isolate_);
   while (it.HasNext()) {
     entry = it.GetNext();
     if (entry.IsField()) {
       field ^= entry.raw();
       cls = field.owner();
       ASSERT(field.is_static());
       field_name = field.name();
-      if ((field_name.CharAt(0) == '_') && !include_private_fields) {
+      if ((field_name.CodeUnitAt(0) == '_') && !include_private_fields) {
         // Skip library-private field.
         continue;
       }
       field_value = GetStaticField(cls, field_name);
       if (!prefix.IsNull()) {
         field_name = String::Concat(prefix, field_name);
       }
       field_list.Add(field_name);
       field_list.Add(field_value);
     }
@@ skipping 372 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart