Sub-minor-key-ify HandlerStubs.

src/field-index.h

Index: src/field-index.h
diff --git a/src/field-index.h b/src/field-index.h
index 78b5db1190c8ec6a3c6a8126d72898440ac984e5..d701f0afd8953dec133b85f1658c6a40c45f2f39 100644
--- a/src/field-index.h
+++ b/src/field-index.h
@@ -26,6 +26,7 @@ class FieldIndex V8_FINAL {
   static FieldIndex ForDescriptor(Map* map, int descriptor_index);
   static FieldIndex ForLoadByFieldIndex(Map* map, int index);
   static FieldIndex ForKeyedLookupCacheIndex(Map* map, int index);
+  static FieldIndex FromFieldAccessStubKey(int key);
 
   int GetLoadByFieldIndex() const;
 
@@ -82,6 +83,8 @@ class FieldIndex V8_FINAL {
       InObjectPropertyBits::encode(inobject_properties);
   }
 
+  explicit FieldIndex(int bit_field) : bit_field_(bit_field) {}
+
   int first_inobject_property_offset() const {
     DCHECK(!IsHiddenField::decode(bit_field_));
     return FirstInobjectPropertyOffsetBits::decode(bit_field_);