Fix issues with compiling V8 with LLVM Clang...

src/factory.h

Index: src/factory.h
===================================================================
--- src/factory.h	(revision 4110)
+++ src/factory.h	(working copy)
@@ -317,7 +317,7 @@
 
 #define ROOT_ACCESSOR(type, name, camel_name)                                  \
   static inline Handle<type> name() {                                          \
-    return Handle<type>(bit_cast<type**, Object**>(                            \
+    return Handle<type>(BitCast<type**, Object**>(                             \
         &Heap::roots_[Heap::k##camel_name##RootIndex]));                       \
   }
   ROOT_LIST(ROOT_ACCESSOR)
@@ -325,7 +325,7 @@
 
 #define SYMBOL_ACCESSOR(name, str) \
   static inline Handle<String> name() {                                        \
-    return Handle<String>(bit_cast<String**, Object**>(                        \
+    return Handle<String>(BitCast<String**, Object**>(                         \
         &Heap::roots_[Heap::k##name##RootIndex]));                             \
   }
   SYMBOL_LIST(SYMBOL_ACCESSOR)