Mark and handle collection of mPrototypeJSFunction just like mPrototypeJSObject is already handled. b=353704 r+sr=jst

js/src/xpconnect/src/xpcwrappednativejsops.cpp

@@ -666,6 +666,12 @@ MarkScopeJSObjects(JSContext *cx, XPCWrappedNativeScope* scope, void *arg)
     {
         JS_MarkGCThing(cx, obj, "XPCWrappedNativeScope::mPrototypeJSObject", arg);
     }
+
+    obj = scope->GetPrototypeJSFunction();
+    if(obj)
+    {
+        JS_MarkGCThing(cx, obj, "XPCWrappedNativeScope::mPrototypeJSFunction", arg);
+    }
 }
 
 void

js/src/xpconnect/src/xpcwrappednativescope.cpp

@@ -121,8 +121,9 @@ XPCWrappedNativeScope::GetNewOrUsed(XPCCallContext& ccx, JSObject* aGlobal)
     else
     {
         // We need to call SetGlobal in order to refresh our cached 
-        // mPrototypeJSObject in the case where the global object is being 
-        // reused (JS_ClearScope has been called).
+        // mPrototypeJSObject and mPrototypeJSFunction in the case where
+        // the global object is being reused (JS_ClearScope has been
+        // called).
         // NOTE: We are only called by nsXPConnect::InitClasses. 
         scope->SetGlobal(ccx, aGlobal);
     }
@@ -137,7 +138,8 @@ XPCWrappedNativeScope::XPCWrappedNativeScope(XPCCallContext& ccx,
         mComponents(nsnull),
         mNext(nsnull),
         mGlobalJSObject(nsnull),
-        mPrototypeJSObject(nsnull)
+        mPrototypeJSObject(nsnull),
+        mPrototypeJSFunction(nsnull)
 {
     // add ourselves to the scopes list
     {   // scoped lock
@@ -317,6 +319,11 @@ XPCWrappedNativeScope::FinishedMarkPhaseOfGC(JSContext* cx, XPCJSRuntime* rt)
         {
             cur->mPrototypeJSObject = nsnull;
         }
+        else if(cur->mPrototypeJSFunction &&
+                JS_IsAboutToBeFinalized(cx, cur->mPrototypeJSFunction))
+        {
+            cur->mPrototypeJSFunction = nsnull;
+        }
         if(cur)
             prev = cur;
         cur = next;
@@ -757,6 +764,7 @@ XPCWrappedNativeScope::DebugDump(PRInt16 depth)
         XPC_LOG_ALWAYS(("mComponents @ %x", mComponents));
         XPC_LOG_ALWAYS(("mGlobalJSObject @ %x", mGlobalJSObject));
         XPC_LOG_ALWAYS(("mPrototypeJSObject @ %x", mPrototypeJSObject));
+        XPC_LOG_ALWAYS(("mPrototypeJSFunction @ %x", mPrototypeJSFunction));
 
         XPC_LOG_ALWAYS(("mWrappedNativeMap @ %x with %d wrappers(s)", \
                          mWrappedNativeMap, \