Clearer warning when components in OWNERS files match multiple teams

R=robertocn@chromium.org

Bug: 1013608
Change-Id: Icf9fd7235a22d91adacc1b1595353e0060147175
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1893375Reviewed-by: Roberto Carrillo <robertocn@chromium.org>
Commit-Queue: Joe Mason <joenotcharles@chromium.org>
Cr-Commit-Position: refs/heads/master@{#711475}

tools/checkteamtags/checkteamtags.py

@@ -147,8 +147,8 @@ def validate_mappings(options, args):
   warnings = ''
   for component, teams in affected_component_to_teams.iteritems():
     if len(teams) > 1:
-      warnings += '\nComponent %s will map to %s' % (
-          component, ', '.join(teams))
+      warnings += ('\nThe set of all OWNERS files with COMPONENT: %s list '
+                   "multiple TEAM's: %s") % (component, ', '.join(teams))
   if warnings:
     warnings = ('Are you sure these are correct? After landing this patch:%s'
                 % warnings)