Comment 2 for bug 1531626

Reviewed: https://review.openstack.org/264376
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=5a9a41563e9c26fb91f4d5ebf863bf24bf395237
Submitter: Jenkins
Branch: master

commit 5a9a41563e9c26fb91f4d5ebf863bf24bf395237
Author: Kevin McDonald <email address hidden>
Date: Wed Jan 6 15:52:55 2016 -0600

    Changes aggregator transformer to allow retention_time w/o size

    When using an aggregator transformer in pipeline.yaml that
    looks like this:
    ---
    transformers:
        - name: "aggregator"
          parameters:
              retention_time: 60
              resource_metadata: last
    ---
    'size' will automatically be defaulted to 1. That means that
    aggregation will not happen as expected with a retention_time of
    60 seconds.

    This fix will only default sample size to 1 if neither
    retention_time or size are defined.

    Change-Id: I4a3aa0f6de26173e6f9383d570ff2cf13d367e38
    Closes-Bug: 1531626