Clear the global objects when unrooting them so that we don't leak via cycles

through the global (which is the parent of the proto for various functions on
the one hand and references various prototypes on the other hand).   Bug
300023, r=shaver, sr=brendan, a=asa

js/src/xpconnect/loader/mozJSComponentLoader.cpp

@@ -198,8 +198,10 @@ mozJSComponentLoader::mozJSComponentLoader()
 static PRIntn PR_CALLBACK
 UnrootGlobals(PLHashEntry *he, PRIntn i, void *arg)
 {
-    JSRuntime *rt = (JSRuntime *)arg;
-    JS_RemoveRootRT(rt, &he->value);
+    JSContext *cx = (JSContext *)arg;
+    JSObject *global = (JSObject *)he->value;
+    JS_ClearScope(cx, global);
+    JS_RemoveRoot(cx, &he->value);
     nsCRT::free((char *)he->key);
     return HT_ENUMERATE_REMOVE;
 }
@@ -997,7 +999,7 @@ mozJSComponentLoader::UnloadAll(PRInt32 aWhen)
         PL_HashTableDestroy(mModules);
         mModules = nsnull;
 
-        PL_HashTableEnumerateEntries(mGlobals, UnrootGlobals, mRuntime);
+        PL_HashTableEnumerateEntries(mGlobals, UnrootGlobals, mContext);
         PL_HashTableDestroy(mGlobals);
         mGlobals = nsnull;