Assert that we destroy ElementAnimations/ElementTransitions through its Destroy() method. (Bug 653644) r=bzbarsky

layout/style/AnimationCommon.h

@@ -148,12 +148,17 @@ struct CommonElementAnimationData : public PRCList
     : mElement(aElement)
     , mElementProperty(aElementProperty)
     , mManager(aManager)
+#ifdef DEBUG
+    , mCalledPropertyDtor(false)
+#endif
   {
     MOZ_COUNT_CTOR(CommonElementAnimationData);
     PR_INIT_CLIST(this);
   }
   ~CommonElementAnimationData()
   {
+    NS_ABORT_IF_FALSE(mCalledPropertyDtor,
+                      "must call destructor through element property dtor");
     MOZ_COUNT_DTOR(CommonElementAnimationData);
     PR_REMOVE_LINK(this);
     mManager->ElementDataRemoved();
@@ -172,6 +177,10 @@ struct CommonElementAnimationData : public PRCList
   nsIAtom *mElementProperty;
 
   CommonAnimationManager *mManager;
+
+#ifdef DEBUG
+  bool mCalledPropertyDtor;
+#endif
 };
 
 }

layout/style/nsAnimationManager.cpp

@@ -159,6 +159,10 @@ ElementAnimationsPropertyDtor(void           *aObject,
                               void           *aData)
 {
   ElementAnimations *ea = static_cast<ElementAnimations*>(aPropertyValue);
+#ifdef DEBUG
+  NS_ABORT_IF_FALSE(!ea->mCalledPropertyDtor, "can't call dtor twice");
+  ea->mCalledPropertyDtor = true;
+#endif
   delete ea;
 }
 

layout/style/nsTransitionManager.cpp

@@ -170,6 +170,10 @@ ElementTransitionsPropertyDtor(void           *aObject,
                                void           *aData)
 {
   ElementTransitions *et = static_cast<ElementTransitions*>(aPropertyValue);
+#ifdef DEBUG
+  NS_ABORT_IF_FALSE(!et->mCalledPropertyDtor, "can't call dtor twice");
+  et->mCalledPropertyDtor = true;
+#endif
   delete et;
 }