DO NOT MERGE Add scan background mode to Settings.Global.

This enables us to mess with the different scan intervals and shift
clients to a different scan mode in the background based on what scan
interval values we choose for the different power modes.

Bug: 71765044
Test: None. Just adding a key.
Change-Id: Id48ebc521dd3fe8a68c9c4c0bdb1018ea5b3743e
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 79b6ea6..50d9767 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -9541,6 +9541,12 @@
         public static final String BLE_SCAN_LOW_LATENCY_INTERVAL_MS =
                 "ble_scan_low_latency_interval_ms";
 
+        /**
+         * The mode that BLE scanning clients will be moved to when in the background.
+         * @hide
+         */
+        public static final String BLE_SCAN_BACKGROUND_MODE = "ble_scan_background_mode";
+
        /**
         * Used to save the Wifi_ON state prior to tethering.
         * This state will be checked to restore Wifi after
diff --git a/core/tests/coretests/src/android/provider/SettingsBackupTest.java b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
index cc36b96..63343be 100644
--- a/core/tests/coretests/src/android/provider/SettingsBackupTest.java
+++ b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
@@ -129,6 +129,7 @@
                     Settings.Global.BLE_SCAN_BALANCED_INTERVAL_MS,
                     Settings.Global.BLE_SCAN_LOW_LATENCY_WINDOW_MS,
                     Settings.Global.BLE_SCAN_LOW_LATENCY_INTERVAL_MS,
+                    Settings.Global.BLE_SCAN_BACKGROUND_MODE,
                     Settings.Global.BLUETOOTH_A2DP_SINK_PRIORITY_PREFIX,
                     Settings.Global.BLUETOOTH_A2DP_SRC_PRIORITY_PREFIX,
                     Settings.Global.BLUETOOTH_A2DP_SUPPORTS_OPTIONAL_CODECS_PREFIX,