[turbofan] Optimize loads of global constants in JSTypedLowering.

src/factory.h

 // Copyright 2014 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.
 
 #ifndef V8_FACTORY_H_
 #define V8_FACTORY_H_
 
 #include "src/isolate.h"
 
 namespace v8 {
@@ skipping 650 matching lines @@
   // irregexp regexp and stores it in the regexp.
   void SetRegExpIrregexpData(Handle<JSRegExp> regexp,
                              JSRegExp::Type type,
                              Handle<String> source,
                              JSRegExp::Flags flags,
                              int capture_count);
 
   // Returns the value for a known global constant (a property of the global
   // object which is neither configurable nor writable) like 'undefined'.
   // Returns a null handle when the given name is unknown.
-  Handle<Object> GlobalConstantFor(Handle<String> name);
+  Handle<Object> GlobalConstantFor(Handle<Name> name);
 
   // Converts the given boolean condition to JavaScript boolean value.
   Handle<Object> ToBoolean(bool value);
 
  private:
   Isolate* isolate() { return reinterpret_cast<Isolate*>(this); }
 
   // Creates a heap object based on the map. The fields of the heap object are
   // not initialized by New<>() functions. It's the responsibility of the caller
   // to do that.
@@ skipping 36 matching lines @@
   // Reinitialize a JSProxy into an (empty) JS object of respective type and
   // size, but keeping the original prototype.  The receiver must have at least
   // the size of the new object.  The object is reinitialized and behaves as an
   // object that has been freshly allocated.
   void ReinitializeJSProxy(Handle<JSProxy> proxy, InstanceType type, int size);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_FACTORY_H_