Create frequently used symbols in the vm isolate

vm/debugger_api_impl.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 "include/dart_debugger_api.h"
 
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/debugger.h"
 #include "vm/isolate.h"
 #include "vm/object_store.h"
+#include "vm/symbols.h"
 
 namespace dart {
 
 #define UNWRAP_AND_CHECK_PARAM(type, var, param)                               \
   type& var = type::Handle();                                                  \
   do {                                                                         \
     const Object& tmp = Object::Handle(Api::UnwrapHandle(param));              \
     if (tmp.IsNull()) {                                                        \
       return Api::NewError("%s expects argument '%s' to be non-null.",         \
                            CURRENT_FUNC, #param);                              \
@@ skipping 581 matching lines @@
     ASSERT(Smi::IsValid(imported.index()));
     import_list.Add(Smi::Handle(Smi::New(imported.index())));
   }
   LibraryPrefixIterator it(lib);
   LibraryPrefix& prefix = LibraryPrefix::Handle(isolate);
   while (it.HasNext()) {
     prefix = it.GetNext();
     prefix_name = prefix.name();
     ASSERT(!prefix_name.IsNull());
     prefix_name = String::Concat(prefix_name,
-                                 String::Handle(isolate, String::New(".")));
+                                 String::Handle(isolate, Symbols::Dot()));
     for (int i = 0; i < prefix.num_libs(); i++) {
       imported = prefix.GetLibrary(i);
       import_list.Add(prefix_name);
       import_list.Add(Smi::Handle(Smi::New(imported.index())));
     }
   }
   return Api::NewHandle(isolate, Array::MakeArray(import_list));
 }
 
 
@@ skipping 58 matching lines @@
   if (lib.IsNull()) {
     return Api::NewError("%s: %d is not a valid library id",
                          CURRENT_FUNC, library_id);
   }
   lib.set_debuggable(is_debuggable);
   return Api::True(isolate);
 }
 
 
 }  // namespace dart