Cache fast scrolling index.
The cache content is also stored in the shared preferences.
The cache is invalidated when:
- contacts (or profile), raw_contacs, or data is modifiled.
- accounts are changed. (Strictly speaking we have to do this only when
an account is being removed, but not when added. But let's just always do this
for just in case.)
- visible contacts are updated; i.e. when custom filter is udpated.
- the locale changes.
Change-Id: I70cfe7c88d3b1a0a0f820338acbe885c136b6e10
6 files changed