Backport @10366 to 3.6

src/factory.h

Index: src/factory.h
===================================================================
--- src/factory.h	(revision 10379)
+++ src/factory.h	(working copy)
@@ -54,8 +54,12 @@
       int size,
       PretenureFlag pretenure = NOT_TENURED);
 
-  Handle<NumberDictionary> NewNumberDictionary(int at_least_space_for);
+  Handle<SeededNumberDictionary> NewSeededNumberDictionary(
+      int at_least_space_for);
 
+  Handle<UnseededNumberDictionary> NewUnseededNumberDictionary(
+      int at_least_space_for);
+
   Handle<StringDictionary> NewStringDictionary(int at_least_space_for);
 
   Handle<ObjectHashTable> NewObjectHashTable(int at_least_space_for);
@@ -412,11 +416,16 @@
       Handle<Object> stack_trace,
       Handle<Object> stack_frames);
 
-  Handle<NumberDictionary> DictionaryAtNumberPut(
-      Handle<NumberDictionary>,
+  Handle<SeededNumberDictionary> DictionaryAtNumberPut(
+      Handle<SeededNumberDictionary>,
       uint32_t key,
       Handle<Object> value);
 
+  Handle<UnseededNumberDictionary> DictionaryAtNumberPut(
+      Handle<UnseededNumberDictionary>,
+      uint32_t key,
+      Handle<Object> value);
+
 #ifdef ENABLE_DEBUGGER_SUPPORT
   Handle<DebugInfo> NewDebugInfo(Handle<SharedFunctionInfo> shared);
 #endif