Bug 1155984. Improve the performance of the "self" getter in both window and workers. r=peterv,jorendorff

dom/base/nsGlobalWindow.cpp

@@ -2620,6 +2620,12 @@ nsGlobalWindow::SetNewDocument(nsIDocument* aDocument,
         NS_ERROR("can't create the 'window' property");
         return NS_ERROR_FAILURE;
       }
+
+      // And same thing for the "self" property.
+      if (!JS_GetProperty(cx, newInnerGlobal, "self", &unused)) {
+        NS_ERROR("can't create the 'self' property");
+        return NS_ERROR_FAILURE;
+      }
     }
   }
 
@@ -3533,11 +3539,9 @@ nsGlobalWindow::GetWindow(nsIDOMWindow** aWindow)
   return NS_OK;
 }
 
-nsIDOMWindow*
-nsGlobalWindow::GetSelf(ErrorResult& aError)
+nsGlobalWindow*
+nsGlobalWindow::Self()
 {
-  FORWARD_TO_OUTER_OR_THROW(GetSelf, (aError), aError, nullptr);
-
   return this;
 }
 
@@ -3545,10 +3549,12 @@ NS_IMETHODIMP
 nsGlobalWindow::GetSelf(nsIDOMWindow** aWindow)
 {
   ErrorResult rv;
-  nsCOMPtr<nsIDOMWindow> window = GetSelf(rv);
+  FORWARD_TO_OUTER_OR_THROW(GetSelf, (aWindow), rv, rv.StealNSResult());
+
+  nsCOMPtr<nsIDOMWindow> window = Self();
   window.forget(aWindow);
 
-  return rv.StealNSResult();
+  return NS_OK;
 }
 
 Navigator*

dom/base/nsGlobalWindow.h

@@ -838,7 +838,7 @@ public:
     CreateNamedPropertiesObject(JSContext *aCx, JS::Handle<JSObject*> aProto);
 
   nsGlobalWindow* Window();
-  nsIDOMWindow* GetSelf(mozilla::ErrorResult& aError);
+  nsGlobalWindow* Self();
   nsIDocument* GetDocument()
   {
     return GetDoc();

dom/bindings/Codegen.py

@@ -3555,11 +3555,12 @@ class CGUpdateMemberSlotsMethod(CGAbstractStaticMethod):
                 "JSJitGetterCallArgs args(&temp);\n")
         for m in self.descriptor.interface.members:
             if m.isAttr() and m.getExtendedAttribute("StoreInSlot"):
-                # Skip doing this for the "window" attribute on the Window
-                # interface, because that can't be gotten safely until we have
-                # hooked it up correctly to the outer window.
+                # Skip doing this for the "window" and "self" attributes on the
+                # Window interface, because those can't be gotten safely until
+                # we have hooked it up correctly to the outer window.  The
+                # window code handles doing the get itself.
                 if (self.descriptor.interface.identifier.name == "Window" and
-                    m.identifier.name == "window"):
+                    (m.identifier.name == "window" or m.identifier.name == "self")):
                     continue
                 body += fill(
                     """

dom/webidl/Window.webidl

@@ -29,8 +29,8 @@ typedef any Transferable;
   // the current browsing context
   [Unforgeable, Constant, StoreInSlot,
    CrossOriginReadable] readonly attribute Window window;
-  [Replaceable, Throws,
-   CrossOriginReadable] readonly attribute WindowProxy self;
+  [Replaceable, Constant, StoreInSlot,
+   CrossOriginReadable] readonly attribute Window self;
   [Unforgeable, StoreInSlot, Pure] readonly attribute Document? document;
   [Throws] attribute DOMString name; 
   [PutForwards=href, Unforgeable, Throws,

dom/webidl/WorkerGlobalScope.webidl

@@ -14,6 +14,7 @@
 
 [Exposed=(Worker)]
 interface WorkerGlobalScope : EventTarget {
+  [Constant, Cached]
   readonly attribute WorkerGlobalScope self;
 
   [Replaceable]

dom/workers/WorkerScope.h

@@ -80,10 +80,10 @@ public:
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(WorkerGlobalScope,
                                                          DOMEventTargetHelper)
 
-  already_AddRefed<WorkerGlobalScope>
+  WorkerGlobalScope*
   Self()
   {
-    return nsRefPtr<WorkerGlobalScope>(this).forget();
+    return this;
   }
 
   Console*

js/public/Class.h

@@ -613,7 +613,7 @@ struct JSClass {
 // JSCLASS_GLOBAL_APPLICATION_SLOTS is the number of slots reserved at
 // the beginning of every global object's slots for use by the
 // application.
-#define JSCLASS_GLOBAL_APPLICATION_SLOTS 4
+#define JSCLASS_GLOBAL_APPLICATION_SLOTS 5
 #define JSCLASS_GLOBAL_SLOT_COUNT      (JSCLASS_GLOBAL_APPLICATION_SLOTS + JSProto_LIMIT * 3 + 31)
 #define JSCLASS_GLOBAL_FLAGS_WITH_SLOTS(n)                                    \
     (JSCLASS_IS_GLOBAL | JSCLASS_HAS_RESERVED_SLOTS(JSCLASS_GLOBAL_SLOT_COUNT + (n)))