[depot_tools] Use logging.warning

logging.warn is deprecated and should be replaced with logging.warning.

Bug:1097402
Change-Id: I55ce007bec47608eeafcf3cd9ac2b90f60073115
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2575621
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
Commit-Queue: Gavin Mak <gavinmak@google.com>
diff --git a/git_cache.py b/git_cache.py
index beee6fe..c332520 100755
--- a/git_cache.py
+++ b/git_cache.py
@@ -360,10 +360,11 @@
       for fetchspec in config_fetchspecs.splitlines():
         self.fetch_specs.add(self.parse_fetch_spec(fetchspec))
     except subprocess.CalledProcessError:
-      logging.warn('Tried and failed to preserve remote.origin.fetch from the '
-                   'existing cache directory.  You may need to manually edit '
-                   '%s and "git cache fetch" again.'
-                   % os.path.join(self.mirror_path, 'config'))
+      logging.warning(
+          'Tried and failed to preserve remote.origin.fetch from the '
+          'existing cache directory.  You may need to manually edit '
+          '%s and "git cache fetch" again.' %
+          os.path.join(self.mirror_path, 'config'))
 
   def _ensure_bootstrapped(
       self, depth, bootstrap, reset_fetch_config, force=False):
@@ -381,7 +382,7 @@
 
     if not should_bootstrap:
       if depth and os.path.exists(os.path.join(self.mirror_path, 'shallow')):
-        logging.warn(
+        logging.warning(
             'Shallow fetch requested, but repo cache already exists.')
       return
 
@@ -408,10 +409,10 @@
         self.RunGit(['init', '--bare'], cwd=self.mirror_path)
       else:
         # Bootstrap failed, previous cache exists; warn and continue.
-        logging.warn(
+        logging.warning(
             'Git cache has a lot of pack files (%d). Tried to re-bootstrap '
-            'but failed. Continuing with non-optimized repository.'
-            % len(pack_files))
+            'but failed. Continuing with non-optimized repository.' %
+            len(pack_files))
 
   def _fetch(self,
              rundir,
@@ -444,7 +445,7 @@
       except subprocess.CalledProcessError:
         if spec == '+refs/heads/*:refs/heads/*':
           raise ClobberNeeded()  # Corrupted cache.
-        logging.warn('Fetch of %s failed' % spec)
+        logging.warning('Fetch of %s failed' % spec)
 
   def populate(self,
                depth=None,
@@ -565,9 +566,9 @@
       f = os.path.join(pack_dir, f)
       try:
         os.remove(f)
-        logging.warn('Deleted stale temporary pack file %s' % f)
+        logging.warning('Deleted stale temporary pack file %s' % f)
       except OSError:
-        logging.warn('Unable to delete temporary pack file %s' % f)
+        logging.warning('Unable to delete temporary pack file %s' % f)
 
 
 @subcommand.usage('[url of repo to check for caching]')
@@ -772,7 +773,7 @@
       if global_cache_dir and (
           os.path.abspath(options.cache_dir) !=
           os.path.abspath(global_cache_dir)):
-        logging.warn('Overriding globally-configured cache directory.')
+        logging.warning('Overriding globally-configured cache directory.')
       Mirror.SetCachePath(options.cache_dir)
 
     return options, args