Support empty PhoneLookupInfo in Cp2PhoneLookup.

This is necessary to support the case when the user has just upgraded to the new UI and there is no PhoneLookupHistory data yet, or they have cleared their data.

Bug: 70570635
Test: unit and manual
PiperOrigin-RevId: 179261139
Change-Id: I1e521d2e86bd3f8643c5c0bb537a52c41f1ceb6d
2 files changed