I've gone through and found a few places where CallQueryInterface() is being called without setting the pointer to null first. This is bad, even if the chances are slim of it failing. Patch attached.
looks good r=rods
Comment on attachment 56856 [details] [diff] [review] Set stuff to null before CallQueryInterface() email@example.com So I noticed that the methods you touched don't set the value of the return arg aFrame/aScrollableView, in the case where the result of the QI is null, but they still return NS_OK. Should we be playing it safe and setting them to nsnull too, just in case the caller didn't initialize them?
I am not sure about that one ... is there a general contract for getter interfaces? My feeling was you were supposed to initialize to null outside. I think we should initialize outside or inside, but not both.
marking verified based on developer's comments