Update license boilerplate text in source code files

Normally we don't do this, but enough changes have accumulated that
we're doing a tree-wide one-off update of the name & style.

BUG=chromium:1098010
TEST=`repo upload` works

Change-Id: I62fe09ab7e5c1b392896cb38cbfd1514eb488add
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/3890326
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Ram Chandrasekar <rchandrasekar@google.com>
diff --git a/scripts/sysmon/proc_metrics_unittest.py b/scripts/sysmon/proc_metrics_unittest.py
index b10abad..339152a 100644
--- a/scripts/sysmon/proc_metrics_unittest.py
+++ b/scripts/sysmon/proc_metrics_unittest.py
@@ -1,4 +1,4 @@
-# Copyright 2017 The Chromium OS Authors. All rights reserved.
+# Copyright 2017 The ChromiumOS Authors
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.