Use symbols when looking up fields in a class

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 2346 matching lines @@
   } else {
     result = Thread::Current()->sticky_error();
   }
   ignore_breakpoints_ = saved_ignore_flag;
   return result.raw();
 }
 
 
 RawObject* Debugger::GetStaticField(const Class& cls,
                                     const String& field_name) {
-  const Field& fld = Field::Handle(cls.LookupStaticField(field_name));
+  const Field& fld =
+      Field::Handle(cls.LookupStaticFieldAllowPrivate(field_name));
   if (!fld.IsNull()) {
     // Return the value in the field if it has been initialized already.
     const Instance& value = Instance::Handle(fld.StaticValue());
     ASSERT(value.raw() != Object::transition_sentinel().raw());
     if (value.raw() != Object::sentinel().raw()) {
       return value.raw();
     }
   }
   // There is no field or the field has not been initialized yet.
   // We must have a getter. Run the getter.
@@ skipping 968 matching lines @@
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart