Issue 6142 - suppress missing Node.js warning when passing -q

ensure_dependencies.py

 #!/usr/bin/env python
 
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import sys
 import os
 import posixpath
 import re
@@ skipping 280 matching lines @@
                '--no-package-lock', '--no-optional']
         subprocess.check_output(cmd, cwd=target)
 
         repo_types[vcs].ignore(os.path.join(target, NPM_LOCKFILE), target)
         repo_types[vcs].ignore(os.path.join(target, 'node_modules'), target)
 
         os.remove(lockfile_path)
     except OSError as e:
         import errno
         if e.errno == errno.ENOENT:
-            logging.error('Failed to install Node.js dependencies for %s,'
-                          ' please ensure Node.js is installed.', target)
+            logging.info('Failed to install Node.js dependencies for %s,'
+                         ' please ensure Node.js is installed.', target)
         else:
             raise
 
 
 def ensure_repo(parentrepo, parenttype, target, type, root, sourcename):
     if os.path.exists(target):
         return False
 
     if SKIP_DEPENDENCY_UPDATES:
         logging.warning('SKIP_DEPENDENCY_UPDATES environment variable set, '
@@ skipping 117 matching lines @@
 
 
 if __name__ == '__main__':
     logging.basicConfig(format='%(levelname)s: %(message)s', level=logging.INFO)
 
     parser = argparse.ArgumentParser(description='Verify dependencies for a set of repositories, by default the repository of this script.')
     parser.add_argument('repos', metavar='repository', type=str, nargs='*', help='Repository path')
     parser.add_argument('-q', '--quiet', action='store_true', help='Suppress informational output')
     args = parser.parse_args()
 
     if args.quiet:

[tlucas, 2017/12/05 14:00:12]

The actual suppression happens here

         logging.disable(logging.INFO)
 
     repos = args.repos
     if not len(repos):
         repos = [os.path.dirname(__file__)]
     for repo in repos:
         resolve_deps(repo)