Clone BackupManagerService and make Trampoline aware of the clone.

RefactoredBackupManagerService is an exact clone of
BackupManagerService. Trampoline chooses between these two based on
backup_refactored_service_disabled global setting, defaulting to true.

Test: manual: flashed the device, ran `settings put global
backup_refactored_service_disabled 1|0`, verified that correct class was
instantiated, ran bmgr backupnow command to make sure that it works.

Bug: 36850431

Change-Id: I8ef91b928a40aae022f88f07a4126a00b1d5e220
diff --git a/core/tests/coretests/src/android/provider/SettingsBackupTest.java b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
index 782a50f..c8771c2 100644
--- a/core/tests/coretests/src/android/provider/SettingsBackupTest.java
+++ b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
@@ -101,6 +101,7 @@
                     Settings.Global.APP_IDLE_CONSTANTS,
                     Settings.Global.ASSISTED_GPS_ENABLED,
                     Settings.Global.AUDIO_SAFE_VOLUME_STATE,
+                    Settings.Global.BACKUP_REFACTORED_SERVICE_DISABLED,
                     Settings.Global.BATTERY_DISCHARGE_DURATION_THRESHOLD,
                     Settings.Global.BATTERY_DISCHARGE_THRESHOLD,
                     Settings.Global.BLE_SCAN_ALWAYS_AVAILABLE,