Previously, clicking into a number field, changing nothing and then
clicking outside the field again would trigger an update (RNA prop
would be set to the same value again). This could potentially cause
an expensive operation (like a modifer) to run again, even if all the
parameters were identical.
The fix prevents this by treating unchanging values in the field as a
cancel operation.
Reviewed By: Severin
Maniphest Tasks: T87448
Differential Revision: https://developer.blender.org/D10976
eb06ccc324