Introduce a code stub version of Array.prototype.push

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 2bdcee6d3c93f09823ada3c95d29255582dce867..29c8850fdda6d30e0c8ef0e6f84875762051a539 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -3080,6 +3080,11 @@ class DescriptorArray: public FixedArray {
     return ToKeyIndex(number_of_descriptors);
   }
 
+  static int ToDetailsIndex(int descriptor_number) {
+    return kFirstIndex + (descriptor_number * kDescriptorSize) +
+           kDescriptorDetails;
+  }
+
  private:
   // An entry in a DescriptorArray, represented as an (array, index) pair.
   class Entry {
@@ -3102,12 +3107,6 @@ class DescriptorArray: public FixedArray {
            kDescriptorKey;
   }
 
-  static int ToDetailsIndex(int descriptor_number) {
-    return kFirstIndex +
-           (descriptor_number * kDescriptorSize) +
-           kDescriptorDetails;
-  }
-
   static int ToValueIndex(int descriptor_number) {
     return kFirstIndex +
            (descriptor_number * kDescriptorSize) +