Policy definition for encryptfs to ext4 migration strategy

chrome/browser/chromeos/policy/proto/chrome_device_policy.proto

Index: chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
diff --git a/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto b/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
index 5909635efa5ed4876a4926303b62a53c70d48740..2330699f75581f3cf12bd73f3904791b10c27b75 100644
--- a/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
+++ b/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
@@ -779,6 +779,19 @@ message DeviceWallpaperImageProto {
   optional string device_wallpaper_image = 1;
 }
 
+// Migration strategy for the case when ARC(N+) needs the ext4 encryption while
+// the device used ecryptfs in the past.
+message DeviceEcryptfsMigrationStrategyProto {
+  enum MigrationStrategy {
+    // ARC is not allowed, no data migration needed.
+    DISALLOW_ARC = 0;
+    // The data migration is allowed, opening the possibility to use ARC.
+    ALLOW_MIGRATION = 1;
+  };
+
+  optional MigrationStrategy migration_strategy = 1;
+}
+
 message ChromeDeviceSettingsProto {
   optional DevicePolicyRefreshRateProto device_policy_refresh_rate = 1;
   optional UserWhitelistProto user_whitelist = 2;
@@ -837,4 +850,6 @@ message ChromeDeviceSettingsProto {
   optional DeviceWallpaperImageProto device_wallpaper_image = 48;
   optional LoginScreenLocalesProto login_screen_locales = 49;
   optional LoginScreenInputMethodsProto login_screen_input_methods = 50;
+  optional DeviceEcryptfsMigrationStrategyProto
+      device_ecryptfs_migration_strategy = 51;
 }