Hello, I would like to make a change to PlusAnonymousUserDataModel. Currently the ID of the anonymous user is fixed to Long.MIN_VALUE. Only one set of temp data can be inserted into the model and used at one time.
I propose the change to enable multiple users to insert into this model concurrently in a thread-safe manner. The idea is to define a pool of available anonymous user IDs. Every time a new anonymous user makes a request, the next available TEMP_USER_ID is pulled from the queue. After recommendations are retrieved, the TEMP_USER_ID can be returned to the pool. As the result this model will become usable in a production multi-user environment. Waiting for your feedback, Aleksei
