Remove Force Dice Migration code

User data shows that user have now been migrated to DICE. This CL
removes the force dice migration code as it is now obsolete.

Fixed: 1122551, 1169179

Change-Id: If3b6b068aeb9e5043bb4a78a7eb2ed6df80073b8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3168858
Commit-Queue: Mihai Sardarescu <[email protected]>
Reviewed-by: David Roger <[email protected]>
Cr-Commit-Position: refs/heads/main@{#924323}
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index ee64606..af47cdf 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -622,6 +622,7 @@
 #if BUILDFLAG(ENABLE_DICE_SUPPORT)
 constexpr char kProfileSwitchInterceptionDeclinedPref[] =
     "signin.ProfileSwitchInterceptionDeclinedPref";
+const char kDiceMigrationCompletePref[] = "signin.DiceMigrationComplete";
 #endif
 
 const char kSuggestionsBlocklist[] = "suggestions.blacklist";
@@ -848,6 +849,7 @@
 
 #if BUILDFLAG(ENABLE_DICE_SUPPORT)
   registry->RegisterDictionaryPref(kProfileSwitchInterceptionDeclinedPref);
+  registry->RegisterDictionaryPref(kDiceMigrationCompletePref);
 #endif
 
   registry->RegisterStringPref(kSuggestionsBlocklist, std::string());
@@ -1709,6 +1711,11 @@
   // Added 09/2021.
   profile_prefs->ClearPref(kAutofillAcceptSaveCreditCardPromptState);
 
+#if BUILDFLAG(ENABLE_DICE_SUPPORT)
+  // Added 09/2021.
+  profile_prefs->ClearPref(kDiceMigrationCompletePref);
+#endif
+
   // Please don't delete the following line. It is used by PRESUBMIT.py.
   // END_MIGRATE_OBSOLETE_PROFILE_PREFS
 }