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Description
Is your feature request related to a problem? Please describe.
In a similar vein as #1006, there are situations where it would be very useful to convert from com.google.cloud.datastore.Entity to com.google.datastore.v1.Entity.
Describe the solution you'd like
Make toPb public.
Describe alternatives you've considered
I currently have interop packages of my own living in com.google.datastore that re-export these methods. It works but isn't great.