Editor will freeze if anim composite has an animation with a notify and length of 0

An anim composite will freeze the editor if one of its animation segments has a a notify and a length of 0 or less. Debugging shows that the engine is stuck inside UAnimSequenceBase::GetAnimNotifies. This is likely because UAnimComposite::IsNotifyAvailable() does not check for a sequence length greater than 0. 

1. Create an animation with a notify in it
2. Create a composite that uses the same skeleton
3. Add the newly create animation to the composite
4. Set the start time and end time of the segment to be equal to each other (e.g. 0.0 and 0.0)

RESULT
The editor will freeze indefinitely