Blender Git Loki

Python API: assume that a crashed Python operator returned FINISHED.

The CANCELLED return value from an operator is intended for
signaling that the operator aborted execution without changing
anything, and an Undo stack entry should not be created.

When a Python operator crashes, it is not safe to assume that
it did nothing, so it should interpret it as FINISHED instead.
Otherwise, the undo system behavior after an operator failure
feels broken.

Differential Revision: https://developer.blender.org/D6241