Update pointers to remove exception handling

A PR for redpotion came in to clean this same kind of code up - we should modify our color method that uses pointers [here](https://github.com/infinitered/rmq/blob/master/motion/ruby_motion_query/color.rb#L163-L177)

to match what was done there: infinitered/redpotion#127

Read motion/ruby_motion_query/color.rb lines 163-177, then compare the intended cleanup in infinitered/redpotion#127. Update the pointer-based color method to match that approach and verify the existing color behavior remains correct.

Written by the indexing model from the issue text.