Show warning message when trying to create SU with existing name

chrome/browser/resources/options/manage_profile_overlay.js

Index: chrome/browser/resources/options/manage_profile_overlay.js
diff --git a/chrome/browser/resources/options/manage_profile_overlay.js b/chrome/browser/resources/options/manage_profile_overlay.js
index df9862b545f1c027297dbf3f5fed425fdef660cf..dad70ea564b32bf28e345222aa2a36b61a05b5be 100644
--- a/chrome/browser/resources/options/manage_profile_overlay.js
+++ b/chrome/browser/resources/options/manage_profile_overlay.js
@@ -379,22 +379,27 @@ cr.define('options', function() {
       var newName = $('create-profile-name').value;
       var i;
       for (i = 0; i < supervisedUsers.length; ++i) {
-        if (supervisedUsers[i].name == newName &&
-            !supervisedUsers[i].onCurrentDevice) {
-          var errorHtml = loadTimeData.getStringF(
-              'manageProfilesExistingSupervisedUser',
-              HTMLEscape(elide(newName, /* maxLength */ 50)));
-          this.showErrorBubble_(errorHtml, 'create', true);
-
+        if (supervisedUsers[i].name == newName) {
           // Check if another supervised user also exists with that name.
           var nameIsUnique = true;
+          var allOnCurrentDevice = supervisedUsers[i].onCurrentDevice;

[Marc Treib, 2015/12/10 11:36:41]

I think this is worth a comment: You're handling the case when there already are
multiple SUs with that name, which "shouldn't" happen (for small values of
"shouldn't"). Took me a moment to understand this :)

[Pam (message me for reviews), 2015/12/15 14:31:37]

It can happen if the first SU with that name hasn't been imported onto this
device.

That said, we don't want to support two SUs with the same name at all. There
might be some existing duplicates, though, from the time this bug has existed.
So we should disallow creating a new SU with a name that exists for any SU (not
just on this device) -- but still allow importing any SU that the current user
already has, even if it duplicates a name.

[atanasova, 2015/12/15 17:57:36]

I added a comment to explain this case. It can happen if the user has already
created supervised users with the same name. That is why we need to check, in
order to allow import if not all are synced on the device.

           var j;
           for (j = i + 1; j < supervisedUsers.length; ++j) {
             if (supervisedUsers[j].name == newName) {
               nameIsUnique = false;
-              break;
+              allOnCurrentDevice = allOnCurrentDevice &&
+                 supervisedUsers[j].onCurrentDevice;
             }
           }
+
+          var errorHtml = allOnCurrentDevice ?
+              loadTimeData.getStringF(
+                  'managedProfilesExistingLocalSupervisedUser') :
+              loadTimeData.getStringF(
+                  'manageProfilesExistingSupervisedUser',
+                  HTMLEscape(elide(newName, /* maxLength */ 50)));
+          this.showErrorBubble_(errorHtml, 'create', true);
+
           $('supervised-user-import-existing').onclick =
               this.getImportHandler_(supervisedUsers[i], nameIsUnique);
           $('create-profile-ok').disabled = true;