[iOS] Add flag for the email in the bookmarks/Rl added snackbar

Following https://bugs.chromium.org/p/chromium/issues/detail?id=1420213#c9,
This CL adds a flag for the new version of bookmarks/RL "item added"
snackbar. The flag will be enabled by default for M113.

Bug: 1420213, 1404311
Change-Id: I92adcaf4192ed0f843882dcbb061120c6aad8721
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4317223
Commit-Queue: Menghan Yang <[email protected]>
Reviewed-by: Boris Sazonov <[email protected]>
Reviewed-by: Arthur Milchior <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1115076}
diff --git a/ios/chrome/browser/flags/about_flags.mm b/ios/chrome/browser/flags/about_flags.mm
index b485e6f..fd101b9 100644
--- a/ios/chrome/browser/flags/about_flags.mm
+++ b/ios/chrome/browser/flags/about_flags.mm
@@ -1426,6 +1426,11 @@
      flag_descriptions::kMixedContentAutoupgradeDescription, flags_ui::kOsIos,
      FEATURE_VALUE_TYPE(
          security_interstitials::features::kMixedContentAutoupgrade)},
+    {"enable-email-in-bookmarks-reading-list-snackbar",
+     flag_descriptions::kEnableEmailInBookmarksReadingListSnackbarName,
+     flag_descriptions::kEnableEmailInBookmarksReadingListSnackbarDescription,
+     flags_ui::kOsIos,
+     FEATURE_VALUE_TYPE(kEnableEmailInBookmarksReadingListSnackbar)},
 };
 
 bool SkipConditionalFeatureEntry(const flags_ui::FeatureEntry& entry) {