Apply signed config on package upgrade/install.

Signature check is not implemented yet, so no configuration can be
applied yet.

Tested with CTS test & follow up changes in later CLs.

For future reference:
Test: atest CtsSignedConfigHostTestCases

Bug: 110509075
Change-Id: I2d2f15d38ec0f1755e21e6e5ab5c82d94aa592a4
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 64aa088..19b12b2 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -12821,6 +12821,13 @@
         public static final String HIDDEN_API_POLICY = "hidden_api_policy";
 
         /**
+         * Current version of signed configuration applied.
+         *
+         * @hide
+         */
+        public static final String SIGNED_CONFIG_VERSION = "signed_config_version";
+
+        /**
          * Timeout for a single {@link android.media.soundtrigger.SoundTriggerDetectionService}
          * operation (in ms).
          *
diff --git a/core/tests/coretests/src/android/provider/SettingsBackupTest.java b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
index f1ed1c2..69bc4a2 100644
--- a/core/tests/coretests/src/android/provider/SettingsBackupTest.java
+++ b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
@@ -414,6 +414,7 @@
                     Settings.Global.SHOW_NOTIFICATION_CHANNEL_WARNINGS,
                     Settings.Global.SHOW_RESTART_IN_CRASH_DIALOG,
                     Settings.Global.SHOW_TEMPERATURE_WARNING,
+                    Settings.Global.SIGNED_CONFIG_VERSION,
                     Settings.Global.SMART_SELECTION_UPDATE_CONTENT_URL,
                     Settings.Global.SMART_SELECTION_UPDATE_METADATA_URL,
                     Settings.Global.SMS_ACCESS_RESTRICTION_ENABLED,