Split SetProperty(...attributes, strictmode) into AddProperty(...attributes) and SetProperty(...…

src/collection-iterator.js

Index: src/collection-iterator.js
diff --git a/src/collection-iterator.js b/src/collection-iterator.js
index 2436a931e28bc4acde80f5c4a8143cc0bff5b8f3..84a3a94c6ee5e2f318ca77d83fb0bfeec57ad09a 100644
--- a/src/collection-iterator.js
+++ b/src/collection-iterator.js
@@ -59,7 +59,7 @@ function SetUpSetIterator() {
   ));
 
   %FunctionSetName(SetIteratorSymbolIterator, '[Symbol.iterator]');
-  %SetProperty(SetIterator.prototype, symbolIterator,
+  %AddProperty(SetIterator.prototype, symbolIterator,
       SetIteratorSymbolIterator, DONT_ENUM);
 }
 
@@ -74,8 +74,7 @@ function ExtendSetPrototype() {
     'values', SetValues
   ));
 
-  %SetProperty($Set.prototype, symbolIterator, SetValues,
-      DONT_ENUM);
+  %AddProperty($Set.prototype, symbolIterator, SetValues, DONT_ENUM);
 }
 
 ExtendSetPrototype();
@@ -139,7 +138,7 @@ function SetUpMapIterator() {
   ));
 
   %FunctionSetName(MapIteratorSymbolIterator, '[Symbol.iterator]');
-  %SetProperty(MapIterator.prototype, symbolIterator,
+  %AddProperty(MapIterator.prototype, symbolIterator,
       MapIteratorSymbolIterator, DONT_ENUM);
 }
 
@@ -155,8 +154,7 @@ function ExtendMapPrototype() {
     'values', MapValues
   ));
 
-  %SetProperty($Map.prototype, symbolIterator, MapEntries,
-      DONT_ENUM);
+  %AddProperty($Map.prototype, symbolIterator, MapEntries, DONT_ENUM);
 }
 
 ExtendMapPrototype();