Fixed log warning for calling doStart() twice.

Bug 36504927

The LoaderManager was performing a doStart() multiple times
and issued a warning and then returned without any problems.
This CL fixes the underlying problem of doStart() being
called multiple times so that the warning isn't logged.

Test: ran fragment and appcompat tests
Change-Id: I3f154e9cb26badbdb8c0b58da95f0a4cd9ac4f6f
1 file changed