Allow compiling with strict aliasing enabled on GCC 4.4.

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index 22511121cb4df6db56d1bfd735193aa456ee677f..c014986f4e6cd885116e97fe1f794d7276f0fd78 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -329,7 +329,7 @@ class Factory : public AllStatic {
 
 #define ROOT_ACCESSOR(type, name, camel_name)                                  \
   static inline Handle<type> name() {                                          \
-    return Handle<type>(BitCast<type**, Object**>(                             \
+    return Handle<type>(BitCast<type**>(                                       \
         &Heap::roots_[Heap::k##camel_name##RootIndex]));                       \
   }
   ROOT_LIST(ROOT_ACCESSOR)
@@ -337,7 +337,7 @@ class Factory : public AllStatic {
 
 #define SYMBOL_ACCESSOR(name, str) \
   static inline Handle<String> name() {                                        \
-    return Handle<String>(BitCast<String**, Object**>(                         \
+    return Handle<String>(BitCast<String**>(                                   \
         &Heap::roots_[Heap::k##name##RootIndex]));                             \
   }
   SYMBOL_LIST(SYMBOL_ACCESSOR)