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..4e9ae665c28f6d89104fb7b4fb7d78c76e73bbbe 100644
--- a/chrome/browser/resources/options/manage_profile_overlay.js
+++ b/chrome/browser/resources/options/manage_profile_overlay.js
@@ -379,27 +379,37 @@ 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);
-
-          // Check if another supervised user also exists with that name.
-          var nameIsUnique = true;
-          var j;
-          for (j = i + 1; j < supervisedUsers.length; ++j) {
-            if (supervisedUsers[j].name == newName) {
-              nameIsUnique = false;
-              break;
-            }
+        if (supervisedUsers[i].name != newName)
+          continue;
+        // Check if another supervised user also exists with that name.
+        var nameIsUnique = true;
+        // Handling the case when multiple supervised users with the same
+        // name exist, but not all of them are on the device.
+        // If at least one is not imported, we want to offer that
+        // option to the user. This could happen due to a bug that allowed
+        // creating SUs with the same name (https://crbug.com/557445).
+        var allOnCurrentDevice = supervisedUsers[i].onCurrentDevice;
+        var j;
+        for (j = i + 1; j < supervisedUsers.length; ++j) {
+          if (supervisedUsers[j].name == newName) {
+            nameIsUnique = false;
+            allOnCurrentDevice = allOnCurrentDevice &&
+               supervisedUsers[j].onCurrentDevice;
           }
-          $('supervised-user-import-existing').onclick =
-              this.getImportHandler_(supervisedUsers[i], nameIsUnique);
-          $('create-profile-ok').disabled = true;
-          return;
         }
+
+        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;
+        return;
       }
     },