The decomposed transform would have consists of nan values if the input
transform had zero scale.
Now the decomposition will check for zero scale, and if it is detected
then the result will be ensured to be finite. Additionally, rotation
value will be copied from previous/next time step to help avoiding
obscure interpolation.
The latter step can become more comprehensive than the current simple
implementation.
Differential Revision: https://developer.blender.org/D8450
