* Save a metadata call when reading files from CloudObjectInputSource.
The call to createSplits(inputFormat, null) in formattableReader would
use the default split hint spec, MaxSizeSplitHintSpec, which makes
getObjectMetadata calls in order to compute its splits. This isn't
necessary; we're just trying to unpack the files inside the input
source.
To fix this, use FilePerSplitHintSpec to extract files without any
funny business.
* Adjust call.
* Fix constant.
* Test coverage.
6517fc2796