[Android] Add flag for detailed language settings feature

This CL adds the DetailedLanguageSettings feature to chrome://flags
on Android.

Bug: 1068667
Change-Id: I6b4bc7aeb0fe00741ea553e89459713834f79e9d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2405942
Reviewed-by: Megan Jablonski <[email protected]>
Commit-Queue: Trevor  Perrier <[email protected]>
Cr-Commit-Position: refs/heads/master@{#806309}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 00350ed..df84181 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -2584,6 +2584,11 @@
 const char kAndroidDefaultBrowserPromoDescription[] =
     "Shows a promo dialog to set Chrome as the default browser";
 
+const char kAndroidDetailedLanguageSettingsName[] =
+    "Detailed Language Settings";
+const char kAndroidDetailedLanguageSettingsDescription[] =
+    "Enable the new detailed language settings page";
+
 const char kAndroidManagedByMenuItemName[] = "Managed by menu item";
 const char kAndroidManagedByMenuItemDescription[] =
     "whether policies have been applied to this browser at the profile or "