[Settings] Fix Deletion Of Passwords

This change augments the fix in https://crrev.com/c/1140853 to cover
other cases the first change missed.

Bug: 862119
Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: I59ca0f37aba90009b645b6ddb4b1413c5325f933
Reviewed-on: https://chromium-review.googlesource.com/1142146Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Jan Wilken Dörrie <jdoerrie@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576419}

chrome/browser/resources/settings/passwords_and_forms_page/passwords_section.js

@@ -153,8 +153,18 @@ Polymer({
     // Create listener functions.
     const setSavedPasswordsListener = list =>
         this.updateList('savedPasswords', item => {
-          return item.entry.loginPair.urls.origin + '_' +
-              item.entry.loginPair.username;
+          // The item uid is built from index, origin, and username for the
+          // following reasons: origin and username are enough to describe and
+          // uniquely identify an entry. It is impossible to have two entries
+          // that have the same origin and username, but different passwords,
+          // as the password update logic prevents these cases. The entry is
+          // required to force a refresh of entries, after a removal or undo of
+          // a removal has taken place. All entries before the point of
+          // modification are uneffected, but the ones following need to be
+          // refreshed. Including the index in the uid achieves this effect.
+          // See https://crbug.com/862119 how this could lead to bugs otherwise.
+          return item.entry.index + '_' + item.entry.loginPair.urls.origin +
+              '_' + item.entry.loginPair.username;
         }, list.map(entry => ({
                       entry: entry,
                       password: '',