This patch adds a test for checking that statement cache
works and it also improves dumpsys diagnostics to include
per database stats as previously it only showed per connection
stats which could have data loss if a connection was dropped
for any reason and not put back in the pool and it also
provides the aggregated view.
Test: dumpsys meminfo
Test: atest SQLiteDatabasePerfTest#testSelectCacheMissRate
Bug: 228498581
Change-Id: Ia49264e8f0e6db83234c2ba5943fd9e25fd5d8b2
506e3f17c5