b/10508861
Temporary fix for this.
For some reason, we're getting messages loaded with the wrong
date being stored. If we have a message with date = 0, and we
filter out anything older than 24 hours, then these messages
with the wrong date won't get loaded into our localMessageMap.
Then we won't recognize that message is already present locally,
and we will fetch a duplicate.
I don't yet know why we're getting the date wrong.
Change-Id: Ic91cd263198ee944eddbaf1d90080e8285a5df6a
0c8df56a0a