Always invoke C++ ArrayPush builtin.

src/x64/stub-cache-x64.cc

Index: src/x64/stub-cache-x64.cc
diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index 5d73b5f0058cb7a38f89bcc8d2a1da077e31e5bb..1517fd3af7dc164ea7ad196f9239b80678673ddf 100644
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -759,18 +759,6 @@ Object* CallStubCompiler::CompileCallConstant(Object* object,
       break;
     }
 
-    case JSARRAY_HAS_FAST_ELEMENTS_CHECK:
-      CheckPrototypes(JSObject::cast(object), rdx, holder,
-                      rbx, rax, name, &miss);
-      // Make sure object->HasFastElements().
-      // Get the elements array of the object.
-      __ movq(rbx, FieldOperand(rdx, JSObject::kElementsOffset));
-      // Check that the object is in fast mode (not dictionary).
-      __ Cmp(FieldOperand(rbx, HeapObject::kMapOffset),
-             Factory::fixed_array_map());
-      __ j(not_equal, &miss);
-      break;
-
     default:
       UNREACHABLE();
   }