[SPARK-20165][SS] Resolve state encoder's deserializer in driver in FlatMapGroupsWithStateExec

## What changes were proposed in this pull request?

- Encoder's deserializer must be resolved at the driver where the class is defined. Otherwise there are corner cases using nested classes where resolving at the executor can fail.

- Fixed flaky test related to processing time timeout. The flakiness is caused because the test thread (that adds data to memory source) has a race condition with the streaming query thread. When testing the manual clock, the goal is to add data and increment clock together atomically, such that a trigger sees new data AND updated clock simultaneously (both or none). This fix adds additional synchronization in when adding data; it makes sure that the streaming query thread is waiting on the manual clock to be incremented (so no batch is currently running) before adding data.

- Added`testQuietly` on some tests that generate a lot of error logs.

## How was this patch tested?
Multiple runs on existing unit tests

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #17488 from tdas/SPARK-20165.