backing out jst's fix for bug 408301 because it seems to have turned some tinderboxen red, others orange, and caused web content regressions

js/src/xpconnect/src/xpcprivate.h

@@ -1151,7 +1151,6 @@ extern JSClass XPC_WN_NoMods_NoCall_Proto_JSClass;
 extern JSClass XPC_WN_ModsAllowed_WithCall_Proto_JSClass;
 extern JSClass XPC_WN_ModsAllowed_NoCall_Proto_JSClass;
 extern JSClass XPC_WN_Tearoff_JSClass;
-extern JSClass XPC_WN_NoHelper_Proto_JSClass;
 
 extern JSObjectOps * JS_DLL_CALLBACK
 XPC_WN_GetObjectOpsNoCall(JSContext *cx, JSClass *clazz);
@@ -1159,9 +1158,6 @@ XPC_WN_GetObjectOpsNoCall(JSContext *cx, JSClass *clazz);
 extern JSObjectOps * JS_DLL_CALLBACK
 XPC_WN_GetObjectOpsWithCall(JSContext *cx, JSClass *clazz);
 
-extern JSObjectOps * JS_DLL_CALLBACK
-XPC_WN_Proto_GetObjectOps(JSContext *cx, JSClass *clazz);
-
 extern JSBool JS_DLL_CALLBACK
 XPC_WN_CallMethod(JSContext *cx, JSObject *obj,
                   uintN argc, jsval *argv, jsval *vp);
@@ -1219,11 +1215,6 @@ public:
     JSObject*
     GetPrototypeJSObject() const {return mPrototypeJSObject;}
 
-    // Getter for the prototype that we use for wrappers that have no
-    // helper.
-    JSObject*
-    GetPrototypeNoHelper(XPCCallContext& ccx);
-
 #ifndef XPCONNECT_STANDALONE
     nsIPrincipal*
     GetPrincipal() const
@@ -1317,13 +1308,8 @@ private:
     // unless a PreCreate hook overrides it.  Note that this _may_ be null (see
     // constructor).
     JSObject*                        mGlobalJSObject;
-
-    // Cached value of Object.prototype
     JSObject*                        mPrototypeJSObject;
-    // Cached value of Function.prototype
     JSObject*                        mPrototypeJSFunction;
-    // Prototype to use for wrappers with no helper.
-    JSObject*                        mPrototypeNoHelper;
 
 #ifndef XPCONNECT_STANDALONE
     // The script object principal instance corresponding to our current global

js/src/xpconnect/src/xpcwrappednative.cpp

@@ -868,11 +868,7 @@ XPCWrappedNative::Init(XPCCallContext& ccx, JSObject* parent, JSBool isGlobal,
 
     JSObject* protoJSObject = HasProto() ?
                                 GetProto()->GetJSProtoObject() :
-                                GetScope()->GetPrototypeNoHelper(ccx);
+                                GetScope()->GetPrototypeJSObject();
-
-    if (!protoJSObject) {
-        return JS_FALSE;
-    }
 
     mFlatJSObject = xpc_NewSystemInheritingJSObject(ccx, jsclazz, protoJSObject,
                                                     parent);

js/src/xpconnect/src/xpcwrappednativejsops.cpp

@@ -899,7 +899,7 @@ JSExtendedClass XPC_WN_NoHelper_JSClass = {
         XPC_WN_NoHelper_Finalize,       // finalize;
 
         /* Optionally non-null members start here. */
-        XPC_WN_GetObjectOpsNoCall,      // getObjectOps;
+        nsnull,                         // getObjectOps;
         nsnull,                         // checkAccess;
         nsnull,                         // call;
         nsnull,                         // construct;
@@ -1186,11 +1186,9 @@ JS_STATIC_DLL_CALLBACK(JSBool)
 XPC_WN_JSOp_Enumerate(JSContext *cx, JSObject *obj, JSIterateOp enum_op,
                       jsval *statep, jsid *idp)
 {
-    JSClass *clazz = JS_GET_CLASS(cx, obj);
+    if(!IS_WRAPPER_CLASS(JS_GET_CLASS(cx, obj)))
-    if(!IS_WRAPPER_CLASS(clazz) || clazz == &XPC_WN_NoHelper_JSClass.base)
     {
-        // obj must be a prototype object or a wrapper w/o a
+        // obj must be a prototype object. Short circuit this call to
-        // helper. Short circuit this call to
         // js_ObjectOps.enumerate().
 
         return js_ObjectOps.enumerate(cx, obj, enum_op, statep, idp);
@@ -1635,8 +1633,7 @@ XPC_WN_Proto_GetObjectOps(JSContext *cx, JSClass *clazz)
         return &XPC_WN_WithCall_JSOps;
 
     NS_ASSERTION(clazz == &XPC_WN_ModsAllowed_NoCall_Proto_JSClass ||
-                 clazz == &XPC_WN_NoMods_NoCall_Proto_JSClass ||
+                 clazz == &XPC_WN_NoMods_NoCall_Proto_JSClass,
-                 clazz == &XPC_WN_NoHelper_Proto_JSClass,
                  "bad proto");
 
     return &XPC_WN_NoCall_JSOps;

js/src/xpconnect/src/xpcwrappednativescope.cpp

@@ -120,11 +120,10 @@ XPCWrappedNativeScope::GetNewOrUsed(XPCCallContext& ccx, JSObject* aGlobal)
     else
     {
         // We need to call SetGlobal in order to refresh our cached 
-        // mPrototypeJSObject and mPrototypeJSFunction and to clear
+        // mPrototypeJSObject and mPrototypeJSFunction in the case where
-        // mPrototypeNoHelper (so we get a new one if requested in the
+        // the global object is being reused (JS_ClearScope has been
-        // new scope) in the case where the global object is being
+        // called).
-        // reused (JS_ClearScope has been called).  NOTE: We are only
+        // NOTE: We are only called by nsXPConnect::InitClasses. 
-        // called by nsXPConnect::InitClasses.
         scope->SetGlobal(ccx, aGlobal);
     }
     return scope;
@@ -140,8 +139,7 @@ XPCWrappedNativeScope::XPCWrappedNativeScope(XPCCallContext& ccx,
         mNext(nsnull),
         mGlobalJSObject(nsnull),
         mPrototypeJSObject(nsnull),
-        mPrototypeJSFunction(nsnull),
+        mPrototypeJSFunction(nsnull)
-        mPrototypeNoHelper(nsnull)
 {
     // add ourselves to the scopes list
     {   // scoped lock
@@ -183,41 +181,6 @@ XPCWrappedNativeScope::SetComponents(nsXPCComponents* aComponents)
     mComponents = aComponents;
 }
 
-// Dummy JS class to let wrappers w/o an xpc prototype share
-// scopes. By doing this we avoid allocating a new scope for every
-// wrapper on creation of the wrapper, and most wrappers won't need
-// their own scope at all for the lifetime of the wrapper.
-// JSCLASS_HAS_PRIVATE is key here (even though there's never anything
-// in the private data slot in these prototypes), as the number of
-// reserved slots in this class needs to match that of the wrappers
-// for the JS engine to share scopes.
-
-JSClass XPC_WN_NoHelper_Proto_JSClass = {
-    "XPC_WN_NoHelper_Proto_JSClass",// name;
-    JSCLASS_HAS_PRIVATE,            // flags;
-
-    /* Mandatory non-null function pointer members. */
-    JS_PropertyStub,                // addProperty;
-    JS_PropertyStub,                // delProperty;
-    JS_PropertyStub,                // getProperty;
-    JS_PropertyStub,                // setProperty;
-    JS_EnumerateStub,               // enumerate;
-    JS_ResolveStub,                 // resolve;
-    JS_ConvertStub,                 // convert;
-    JS_FinalizeStub,                // finalize;
-
-    /* Optionally non-null members start here. */
-    XPC_WN_Proto_GetObjectOps,      // getObjectOps;
-    nsnull,                         // checkAccess;
-    nsnull,                         // call;
-    nsnull,                         // construct;
-    nsnull,                         // xdrObject;
-    nsnull,                         // hasInstance;
-    nsnull,                         // mark/trace;
-    nsnull                          // spare;
-};
-
-
 void
 XPCWrappedNativeScope::SetGlobal(XPCCallContext& ccx, JSObject* aGlobal)
 {
@@ -228,10 +191,11 @@ XPCWrappedNativeScope::SetGlobal(XPCCallContext& ccx, JSObject* aGlobal)
 #ifndef XPCONNECT_STANDALONE
     mScriptObjectPrincipal = nsnull;
     // Now init our script object principal, if the new global has one
-
+    if (aGlobal)
+    {
         JSContext* cx = ccx.GetJSContext();
         const JSClass* jsClass = JS_GetClass(cx, aGlobal);
-    if(!(~jsClass->flags & (JSCLASS_HAS_PRIVATE |
+        if (jsClass && !(~jsClass->flags & (JSCLASS_HAS_PRIVATE |
                                             JSCLASS_PRIVATE_IS_NSISUPPORTS)))
         {
             // Our global has an nsISupports native pointer.  Let's
@@ -239,15 +203,15 @@ XPCWrappedNativeScope::SetGlobal(XPCCallContext& ccx, JSObject* aGlobal)
             nsISupports* priv = (nsISupports*)JS_GetPrivate(cx, aGlobal);
             nsCOMPtr<nsIXPConnectWrappedNative> native =
                 do_QueryInterface(priv);
-        if(native)
+            if (native)
             {
                 mScriptObjectPrincipal = do_QueryWrappedNative(native);
             }
-        if(!mScriptObjectPrincipal)
+            if (!mScriptObjectPrincipal) {
-        {
                 mScriptObjectPrincipal = do_QueryInterface(priv);
             }
         }
+    }
 #endif
 
     // Lookup 'globalObject.Object.prototype' for our wrapper's proto
@@ -283,10 +247,6 @@ XPCWrappedNativeScope::SetGlobal(XPCCallContext& ccx, JSObject* aGlobal)
             NS_ERROR("Can't get globalObject.Function.prototype");
         }
     }
-
-    // Clear the no helper wrapper prototype object so that a new one
-    // gets created if needed.
-    mPrototypeNoHelper = nsnull;
 }
 
 XPCWrappedNativeScope::~XPCWrappedNativeScope()
@@ -319,25 +279,6 @@ XPCWrappedNativeScope::~XPCWrappedNativeScope()
     NS_IF_RELEASE(mComponents);
 }
 
-JSObject *
-XPCWrappedNativeScope::GetPrototypeNoHelper(XPCCallContext& ccx)
-{
-    // We could create this prototype in SetGlobal(), but all scopes
-    // don't need one, so we save ourselves a bit of space if we
-    // create these when they're needed.
-    if(!mPrototypeNoHelper)
-    {
-        mPrototypeNoHelper =
-            xpc_NewSystemInheritingJSObject(ccx, &XPC_WN_NoHelper_Proto_JSClass,
-                                            mPrototypeJSObject,
-                                            mGlobalJSObject);
-
-        NS_ASSERTION(mPrototypeNoHelper,
-                     "Failed to create prototype for wrappers w/o a helper");
-    }
-
-    return mPrototypeNoHelper;
-}
 
 JS_STATIC_DLL_CALLBACK(JSDHashOperator)
 WrappedNativeJSGCThingTracer(JSDHashTable *table, JSDHashEntryHdr *hdr,
@@ -466,11 +407,6 @@ XPCWrappedNativeScope::FinishedMarkPhaseOfGC(JSContext* cx, XPCJSRuntime* rt)
             {
                 cur->mPrototypeJSFunction = nsnull;
             }
-            if(cur->mPrototypeNoHelper &&
-               JS_IsAboutToBeFinalized(cx, cur->mPrototypeNoHelper))
-            {
-                cur->mPrototypeNoHelper = nsnull;
-            }
         }
         if(cur)
             prev = cur;
@@ -701,12 +637,11 @@ GetScopeOfObject(JSContext* cx, JSObject* obj)
     {
 #ifdef DEBUG
         {
-            if(!(~clazz->flags & (JSCLASS_HAS_PRIVATE |
+            if(clazz->flags & JSCLASS_HAS_PRIVATE &&
-                                  JSCLASS_PRIVATE_IS_NSISUPPORTS)) &&
+               clazz->flags & JSCLASS_PRIVATE_IS_NSISUPPORTS)
-               (supports = (nsISupports*) JS_GetPrivate(cx, obj)))
             {
                 nsCOMPtr<nsIXPConnectWrappedNative> iface =
-                    do_QueryInterface(supports);
+                    do_QueryInterface((nsISupports*) JS_GetPrivate(cx, obj));
 
                 NS_ASSERTION(!iface, "Uh, how'd this happen?");
             }
@@ -926,7 +861,6 @@ XPCWrappedNativeScope::DebugDump(PRInt16 depth)
         XPC_LOG_ALWAYS(("mGlobalJSObject @ %x", mGlobalJSObject));
         XPC_LOG_ALWAYS(("mPrototypeJSObject @ %x", mPrototypeJSObject));
         XPC_LOG_ALWAYS(("mPrototypeJSFunction @ %x", mPrototypeJSFunction));
-        XPC_LOG_ALWAYS(("mPrototypeNoHelper @ %x", mPrototypeNoHelper));
 
         XPC_LOG_ALWAYS(("mWrappedNativeMap @ %x with %d wrappers(s)", \
                          mWrappedNativeMap, \