Create frequently used symbols in the vm isolate

vm/scopes.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/scopes.h"
 
 #include "vm/ast.h"
 #include "vm/bit_vector.h"
 #include "vm/object.h"
 #include "vm/parser.h"
+#include "vm/symbols.h"
 
 namespace dart {
 
 const char* SourceLabel::kDefaultLabelName = ":L";
 
 const char* LocalVariable::kSavedContextVarName = ":saved_entry_context_var";
 
 
 int SourceLabel::FunctionLevel() const {
   ASSERT(owner() != NULL);
@@ skipping 483 matching lines @@
 
 
 RawContextScope* LocalScope::CreateImplicitClosureScope(const Function& func) {
   static const intptr_t kNumCapturedVars = 1;
 
   // Create a ContextScope with space for kNumCapturedVars descriptors.
   const ContextScope& context_scope =
       ContextScope::Handle(ContextScope::New(kNumCapturedVars));
 
   // Create a descriptor for 'this' variable.
-  const String& name = String::Handle(String::NewSymbol("this"));
+  const String& name = String::Handle(Symbols::New("this"));
   context_scope.SetTokenIndexAt(0, func.token_pos());
   context_scope.SetNameAt(0, name);
   context_scope.SetIsFinalAt(0, true);
   const AbstractType& type = AbstractType::Handle(func.ParameterTypeAt(0));
   context_scope.SetTypeAt(0, type);
   context_scope.SetContextIndexAt(0, 0);
   context_scope.SetContextLevelAt(0, 0);
   ASSERT(context_scope.num_variables() == kNumCapturedVars);  // Verify count.
   return context_scope.raw();
 }
@@ skipping 26 matching lines @@
   } else {
     // Shift negative indexes so that the lowest one is 0 (they are still
     // non-positive) and index them backward from the end of the vector.
     return (var_count - 1) +
         (index() - ParsedFunction::kFirstLocalSlotIndex);
   }
 }
 
 
 }  // namespace dart