Add variation of already-allowed license exception for NaCl.

BUG=none
TEST=Linux builder goes green
TBR

Review URL: https://chromiumcodereview.appspot.com/10273009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@134529 0039d316-1c4b-4281-b951-d872f2087c98

tools/checklicenses/checklicenses.py

@@ -136,6 +136,8 @@ PATH_SPECIFIC_WHITELISTED_LICENSES = {
 
         # TODO(phajdan.jr): Make licensecheck not print the comma after 3.1.
         'GPL (v3.1,)',
+
+        'GPL (v3 or later)',
     ],
     'net/disk_cache/hash.cc': [  # http://crbug.com/98100
         'UNKNOWN',