Remove CONST_LEGACY VariableMode

src/compiler/js-global-object-specialization.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/js-global-object-specialization.h"
 
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/js-graph.h"
@@ skipping 228 matching lines @@
   Handle<ScriptContextTable> script_context_table(
       global_object->native_context()->script_context_table(), isolate());
   ScriptContextTable::LookupResult lookup_result;
   if (!ScriptContextTable::Lookup(script_context_table,
                                   Handle<String>::cast(name), &lookup_result)) {
     return false;
   }
   Handle<Context> script_context = ScriptContextTable::GetContext(
       script_context_table, lookup_result.context_index);
   result->context = script_context;
-  result->immutable = IsImmutableVariableMode(lookup_result.mode);
+  result->immutable = lookup_result.mode == CONST;
   result->index = lookup_result.slot_index;
   return true;
 }
 
 
 Graph* JSGlobalObjectSpecialization::graph() const {
   return jsgraph()->graph();
 }
 
 
@@ skipping 12 matching lines @@
 }
 
 
 SimplifiedOperatorBuilder* JSGlobalObjectSpecialization::simplified() const {
   return jsgraph()->simplified();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8