Added the flag #enable-new-mac-notification-api

This flag will be used to determine which notification API to run on macOS devices during the introduction of the new API.

Bug: None
Change-Id: Iddadbec08cea46d99a46cf425466420cdc38347d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2396076
Reviewed-by: Avi Drissman <[email protected]>
Reviewed-by: Richard Knoll <[email protected]>
Commit-Queue: Mohamed Adel <[email protected]>
Cr-Commit-Position: refs/heads/master@{#804936}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 4c90f8f..78eedbcb 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -5816,6 +5816,13 @@
      FEATURE_VALUE_TYPE(features::kMacCoreLocationImplementation)},
 #endif
 
+#if defined(OS_MAC)
+    {"enable-new-mac-notification-api",
+     flag_descriptions::kNewMacNotificationAPIName,
+     flag_descriptions::kNewMacNotificationAPIDescription, kOsMac,
+     FEATURE_VALUE_TYPE(features::kNewMacNotificationAPI)},
+#endif
+
 #if defined(OS_CHROMEOS)
     {"exo-ordinal-motion", flag_descriptions::kExoOrdinalMotionName,
      flag_descriptions::kExoOrdinalMotionDescription, kOsCrOS,