Fix 'Modifying dpm.setSecureSetting call for install_non_market_apps'

The previous change was reverted as it broke work profile provisioning.
Clearing binder calling identity before calling into settings provider
should fix the issue.

Test: runtest managed-provisioning
Test: runtest -x services/tests/servicestests/src/com/android/server/devicepolicy/DevicePolicyManagerTest.java
Test: Manually tested that work profile is inflated with expected values
of install_non_market_apps

Bug: 33947615
Bug: 35590590

Change-Id: I3c31a73fef0c25c0e682e18f637272adad39b28d
diff --git a/core/tests/coretests/src/android/provider/SettingsBackupTest.java b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
index 76331a8..3584569 100644
--- a/core/tests/coretests/src/android/provider/SettingsBackupTest.java
+++ b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
@@ -460,6 +460,7 @@
                  Settings.Secure.TV_INPUT_CUSTOM_LABELS,
                  Settings.Secure.TV_INPUT_HIDDEN_INPUTS,
                  Settings.Secure.UI_NIGHT_MODE, // candidate?
+                 Settings.Secure.UNKNOWN_SOURCES_DEFAULT_REVERSED,
                  Settings.Secure.UNSAFE_VOLUME_MUSIC_ACTIVE_MS,
                  Settings.Secure.USB_AUDIO_AUTOMATIC_ROUTING_DISABLED,
                  Settings.Secure.USER_SETUP_COMPLETE,