(Part 2.6 - Final one!) Use new socket schema in ValueMetricProducer_test

First CL at ag/10697747. Sending ValueMetricProducer_test as multiple CLs to retain diff and make
it easier to review.

Updates from TestInvalidBucketWhenMultipleBucketsSkipped to TestSlicedStateWithPrimaryField_WithDimensions

Test: bit statsd_test:*
Bug: 149590301
Change-Id: I682a19ea6fe39dd750ca396c9de479befa658f0d