[ios] Always remove keyboard on password search edit

Bug: 885088
Cq-Include-Trybots: luci.chromium.try:ios-simulator-cronet;luci.chromium.try:ios-simulator-full-configs
Change-Id: I5d11b0b736b1b040674aef1911ca8a9510e9402c
Reviewed-on: https://chromium-review.googlesource.com/1230676
Commit-Queue: David Jean <djean@chromium.org>
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#592354}

ios/chrome/browser/ui/settings/save_passwords_collection_view_controller.mm

@@ -1051,7 +1051,21 @@ blacklistedFormItemWithText:(NSString*)text
       base::mac::ObjCCastStrict<SettingsSearchItem>(
           [model itemAtIndexPath:itemPath]);
   [searchItem setEnabled:enabled];
-  [self reconfigureCellsForItems:@[ searchItem ]];
+
+  NSIndexPath* indexPath =
+      [self.collectionViewModel indexPathForItem:searchItem];
+  MDCCollectionViewCell* cell =
+      base::mac::ObjCCastStrict<MDCCollectionViewCell>(
+          [self.collectionView cellForItemAtIndexPath:indexPath]);
+
+  // |cell| may be nil if the row is not currently on screen. If that's the case
+  // and we are disabling we force the keyboard down (since the cell can't do it
+  // for us).
+  if (cell) {
+    [searchItem configureCell:cell];
+  } else if (!enabled) {
+    [self.view endEditing:YES];
+  }
 }
 
 #pragma mark - Testing