- adds a loading state to search so the user isn't left with a blank
screen for several seconds
- adds a timeout so that a warning message is shown for results that
take over 10 seconds
- use default loading/no message views in ListFragment so we don't have
to manager our own stuff
Bug: 5014107
Bug: 5037618
Change-Id: I8b03fa0967055989156c7777901affc777c4fae7