Blender Git Loki

Fix T69542: Corrective Smooth modifier breaks when drivers are involved

Previously the cache for the modifier would not be invalidated if
modifier settings were changed with drivers or keyframes.

Now we compare the current setting with the ones used to generate the
cache and invalidate the cache if they differ.

Reviewed By: Sybren

Differential Revision: https://developer.blender.org/D5694