[presubmit] Base64 encode for config validation

Bug: 782328
Change-Id: I5219416371cc1b3dfc1f93fee6d1067ef5a6e3d3
Reviewed-on: https://chromium-review.googlesource.com/758719
Commit-Queue: Mun Yong Jang <myjang@google.com>
Reviewed-by: Nodir Turakulov <nodir@chromium.org>

presubmit_canned_checks.py

@@ -40,9 +40,10 @@ BLACKLIST_LINT_FILTERS = [
 ### Description checks
 
 def CheckChangedConfigs(input_api, output_api):
-  import urllib2
-  import json
   import collections
+  import base64
+  import json
+  import urllib2
 
   import auth
   import git_cl
@@ -107,7 +108,8 @@ def CheckChangedConfigs(input_api, output_api):
       if dr == '/' or file_path.startswith(dr):
         cs_to_files[cs].append({
           'path': file_path[len(dr):] if dr != '/' else file_path,
-          'content': '\n'.join(f.NewContents())
+          'content': base64.b64encode(
+              '\n'.join(f.NewContents()).encode('utf-8'))
         })
   outputs = []
   for cs, f in cs_to_files.iteritems():