cros: Enable encryption migration UI by default.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index d23def339685f91f885931707bcfe16649b4359b..a42eda9dc4033e47a869d729a9d38549c057d223 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -2279,7 +2279,9 @@ const FeatureEntry kFeatureEntries[] = {
     {"enable-encryption-migration",
      flag_descriptions::kEnableEncryptionMigrationName,
      flag_descriptions::kEnableEncryptionMigrationDescription, kOsCrOS,
-     SINGLE_VALUE_TYPE(chromeos::switches::kEnableEncryptionMigration)},
+     ENABLE_DISABLE_VALUE_TYPE(
+         chromeos::switches::kEnableEncryptionMigration,
+         chromeos::switches::kDisableEncryptionMigration)},
 #endif  // OS_CHROMEOS
 #if !defined(OS_ANDROID) && !defined(OS_IOS) && defined(GOOGLE_CHROME_BUILD)
     {"enable-google-branded-context-menu",