geekdroid-firebase: allow to validate QueryPagingSource boundary key This is useful when ordering by @ServerTimestamp field. When the document hasn't been sent to server it can't be used as a boundary key has the server timestamp is null. This change allows client to make the check and avoid an IllegalArgumentException.

Config
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This directory contains various configuration files for gradle and its plugins :

  * checkstyle configuration
  * task to get a source archive of the project