Summary:
opt-stats.py and opt-viewer.py's argument parsers both take a positional
argument 'yaml_files'. Positional arguments in Python's argparse module are
required by default, so the subsequent checks for `len(args.yaml_files) == 0`
are unnecessary -- if the length was zero, then the call to
`parser.parse_args()` would have thrown an error already.
Because there is no way for `len(args.yaml_files)` to be zero at these
points, removing the code is NFC.
Reviewers: anemet, davidxl
Reviewed By: anemet
Subscribers: llvm-commits, fhahn
Differential Revision: https://reviews.llvm.org/D34567
llvm-svn: 306147
7e66b6b8ea