Remove onDeviceOffBody()

Remove KeyStore#onDeviceOffBody(), since its only caller was removed by
http://ag/24518980.  Also remove
AndroidKeyStoreMaintenance#onDeviceOffBody() which was only called by
KeyStore#onDeviceOffBody().

Bug: 289849354
Test: Build
Change-Id: I3db2672b8038e947a974f703aa2c273ecb65414e

keystore/java/android/security/AndroidKeyStoreMaintenance.java

@@ -174,20 +174,6 @@ public class AndroidKeyStoreMaintenance {
         }
     }
 
-    /**
-     * Informs Keystore 2.0 that an off body event was detected.
-     */
-    public static void onDeviceOffBody() {
-        StrictMode.noteDiskWrite();
-        try {
-            getService().onDeviceOffBody();
-        } catch (Exception e) {
-            // TODO This fails open. This is not a regression with respect to keystore1 but it
-            //      should get fixed.
-            Log.e(TAG, "Error while reporting device off body event.", e);
-        }
-    }
-
     /**
      * Migrates a key given by the source descriptor to the location designated by the destination
      * descriptor.

keystore/java/android/security/KeyStore.java

@@ -56,11 +56,4 @@ public class KeyStore {
 
         return Authorization.addAuthToken(authToken);
     }
-
-    /**
-     * Notify keystore that the device went off-body.
-     */
-    public void onDeviceOffBody() {
-        AndroidKeyStoreMaintenance.onDeviceOffBody();
-    }
 }