Initialize keyguard preview w/ sample weather data as fallback

In some preview cases weather data can be slow to load, or not load at
all. In these cases, we'll now fallback to using the sample data that
WPP already uses in some places.

Bug: 285877857
Flag: NONE small bugfix
Test: Manually checked preview case in bug
Change-Id: Ib5fa498ffd390d3a911abac315b5095bede0ac30