Bug 536437 - work around a bug in the Mozilla plugin host where NPN_GetURLNotify can return an error and also call NPP_URLNotify, r=cjones

--HG--
extra : transplant_source : %07%7B%DBO%AF%069%16%F5%FF%1A%C5%F5Wi%E1%9D%E1%E6%83

dom/plugins/PluginInstanceParent.cpp

@@ -270,6 +270,10 @@ PluginInstanceParent::AnswerPStreamNotifyConstructor(PStreamNotifyParent* actor,
                                                      const bool& file,
                                                      NPError* result)
 {
+    bool streamDestroyed = false;
+    static_cast<StreamNotifyParent*>(actor)->
+        SetDestructionFlag(&streamDestroyed);
+
     if (!post) {
         *result = mNPNIface->geturlnotify(mNPP,
                                           NullableStringGet(url),
@@ -285,8 +289,11 @@ PluginInstanceParent::AnswerPStreamNotifyConstructor(PStreamNotifyParent* actor,
                                            file, actor);
     }
 
-    if (*result != NPERR_NO_ERROR)
-        PStreamNotifyParent::Call__delete__(actor, NPERR_GENERIC_ERROR);
+    if (!streamDestroyed) {
+        static_cast<StreamNotifyParent*>(actor)->ClearDestructionFlag();
+        if (*result != NPERR_NO_ERROR)
+            PStreamNotifyParent::Call__delete__(actor, NPERR_GENERIC_ERROR);
+    }
 
     return true;
 }

dom/plugins/StreamNotifyParent.h

@@ -48,7 +48,26 @@ class StreamNotifyParent : public PStreamNotifyParent
 {
   friend class PluginInstanceParent;
 
-  StreamNotifyParent() { }
+  StreamNotifyParent()
+    : mDestructionFlag(NULL)
+  { }
+  ~StreamNotifyParent() {
+    if (mDestructionFlag)
+      *mDestructionFlag = true;
+  }
+
+public:
+  // If we are destroyed within the call to NPN_GetURLNotify, notify the caller
+  // so that we aren't destroyed again. see bug 536437.
+  void SetDestructionFlag(bool* flag) {
+    mDestructionFlag = flag;
+  }
+  void ClearDestructionFlag() {
+    mDestructionFlag = NULL;
+  }
+
+private:
+  bool* mDestructionFlag;
 };
 
 } // namespace plugins