Replace PushIfAbsent by a Stack object

src/runtime/runtime-array.cc

Index: src/runtime/runtime-array.cc
diff --git a/src/runtime/runtime-array.cc b/src/runtime/runtime-array.cc
index 52d921885da1f6009cc4c9504b0dff65c6f80123..a0b3080a092a4a1fa910338cfb18914038e601e6 100644
--- a/src/runtime/runtime-array.cc
+++ b/src/runtime/runtime-array.cc
@@ -88,29 +88,6 @@ RUNTIME_FUNCTION(Runtime_TransitionElementsKind) {
 }
 
 
-// Push an object unto an array of objects if it is not already in the
-// array.  Returns true if the element was pushed on the stack and
-// false otherwise.
-RUNTIME_FUNCTION(Runtime_PushIfAbsent) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 2);
-  CONVERT_ARG_HANDLE_CHECKED(JSArray, array, 0);
-  CONVERT_ARG_HANDLE_CHECKED(JSReceiver, element, 1);
-  RUNTIME_ASSERT(array->HasFastSmiOrObjectElements());
-  int length = Smi::cast(array->length())->value();
-  FixedArray* elements = FixedArray::cast(array->elements());
-  for (int i = 0; i < length; i++) {
-    if (elements->get(i) == *element) return isolate->heap()->false_value();
-  }
-
-  // Strict not needed. Used for cycle detection in Array join implementation.
-  RETURN_FAILURE_ON_EXCEPTION(
-      isolate, JSObject::AddDataElement(array, length, element, NONE));
-  JSObject::ValidateElements(array);
-  return isolate->heap()->true_value();
-}
-
-
 // Moves all own elements of an object, that are below a limit, to positions
 // starting at zero. All undefined values are placed after non-undefined values,
 // and are followed by non-existing element. Does not change the length