Fix Non-Deterministic Pivot Test

This failed on build servers (small, slow, single or dual-core machines).
Merge pull request #987 from benjchristensen/pivot

Fix Non-Deterministic Pivot Test
OnErrorFailedException

Re-throw when onError throws an Exception.
This fixes https://github.com/Netflix/RxJava/issues/969
Merge pull request #988 from benjchristensen/issue-969

OnErrorFailedException
[Gradle Release Plugin] - pre tag commit:  '0.17.2'.
[Gradle Release Plugin] - new version commit:  '0.17.3-SNAPSHOT'.
0.17.2