bug 1243077 - add AccessibleOrProxy::IsNull() r=davidb

accessible/atk/AccessibleWrap.cpp

@@ -567,7 +567,7 @@ finalizeCB(GObject *aObj)
 {
     if (!IS_MAI_OBJECT(aObj))
         return;
-    NS_ASSERTION(MAI_ATK_OBJECT(aObj)->accWrap.Bits() == 0, "AccWrap NOT null");
+    NS_ASSERTION(MAI_ATK_OBJECT(aObj)->accWrap.IsNull(), "AccWrap NOT null");
 
     // call parent finalize function
     // finalize of GObjectClass will unref the accessible parent if has

accessible/base/AccessibleOrProxy.h

@@ -48,6 +48,8 @@ public:
     return nullptr;
   }
 
+  bool IsNull() const { return mBits == 0; }
+
   // XXX these are implementation details that ideally would not be exposed.
   uintptr_t Bits() const { return mBits; }
   void SetBits(uintptr_t aBits) { mBits = aBits; }