Remove the global Strength enum class completely.

src/json-parser.h

Index: src/json-parser.h
diff --git a/src/json-parser.h b/src/json-parser.h
index efd3c04b98f7e323a79076e5672df745c9611810..5693933ee0b927575e9961da02427684b07c2980 100644
--- a/src/json-parser.h
+++ b/src/json-parser.h
@@ -536,7 +536,7 @@ Handle<Object> JsonParser<seq_one_byte>::ParseJsonArray() {
     fast_elements->set(i, *elements[i]);
   }
   Handle<Object> json_array = factory()->NewJSArrayWithElements(
-      fast_elements, FAST_ELEMENTS, Strength::WEAK, pretenure_);
+      fast_elements, FAST_ELEMENTS, pretenure_);
   return scope.CloseAndEscape(json_array);
 }