Scan Optimization: expose API to update device mobility state

Exposed API in WifiManager to allow device mobility state to
be updated, so that Wifi scan interval can be increased when the
device is stationary in order to save power. Also added a new
permission to protect this API from being used by unauthorized
applications.

Bug: 120097108
Test: Call new API method using test app
Change-Id: Iee59dba711c23add5d4b2affafeac2c009407c7f
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index dca15bd..3834ad1 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -1642,6 +1642,12 @@
     <permission android:name="android.permission.NETWORK_BYPASS_PRIVATE_DNS"
         android:protectionLevel="signature" />
 
+    <!-- #SystemApi @hide Allows device mobility state to be set so that Wifi scan interval can be increased
+         when the device is stationary in order to save power.
+         <p>Not for use by third-party applications. -->
+    <permission android:name="android.permission.WIFI_SET_DEVICE_MOBILITY_STATE"
+        android:protectionLevel="signature|privileged" />
+
     <!-- ======================================= -->
     <!-- Permissions for short range, peripheral networks -->
     <!-- ======================================= -->