Summary:
The logs plugin had an inconsistency where you'd be tailing the logs, and then hit "Clear Logs", which would empty the screen, but as the page fills up again, it would stay in the current position and not scroll with the new ones coming in.
This makes it consistent by making the behaviour:
```
If not props.stickyBottom
never autoscroll, e.g. for static tables of data
else
if scrolled to the bottom
autoscroll
if all the rows fit into the screen at once
autoscroll
```
Reviewed By: passy
Differential Revision: D15856813
fbshipit-source-id: 1357b0e39b576dbe69d260545b21fdab808d2bd2
6bdaa6aff1