Scan Optimization: Check set device mobility permission is granted to <= 1 app

Add a new CTS test to ensure that set device mobility permission is
granted to at most 1 app.

Bug: 120097108
Test: "atest WifiManagerTest" after installing app with new
permission granted
Change-Id: Ifda2163da6da9e9365c440d47031d25f92c6c375

tests/cts/net/src/android/net/wifi/cts/WifiManagerTest.java

@@ -58,6 +58,7 @@ import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.stream.Collectors;
 
 public class WifiManagerTest extends AndroidTestCase {
     private static class MySync {
@@ -998,6 +999,30 @@ public class WifiManagerTest extends AndroidTestCase {
         }
     }
 
+    /**
+     * Verify that the {@link android.Manifest.permission#WIFI_SET_DEVICE_MOBILITY_STATE} permission
+     * is held by at most one application.
+     */
+    public void testWifiSetDeviceMobilityStatePermission() {
+        final PackageManager pm = getContext().getPackageManager();
+
+        final List<PackageInfo> holding = pm.getPackagesHoldingPermissions(new String[] {
+                android.Manifest.permission.WIFI_SET_DEVICE_MOBILITY_STATE
+        }, PackageManager.MATCH_UNINSTALLED_PACKAGES);
+
+        List<String> uniquePackageNames = holding
+                .stream()
+                .map(pi -> pi.packageName)
+                .distinct()
+                .collect(Collectors.toList());
+
+        if (uniquePackageNames.size() > 1) {
+            fail("The WIFI_SET_DEVICE_MOBILITY_STATE permission must not be held by more than one "
+                    + "application, but is held by " + uniquePackageNames.size() + " applications: "
+                    + String.join(", ", uniquePackageNames));
+        }
+    }
+
     private void turnScreenOnNoDelay() throws Exception {
         mUiDevice.executeShellCommand("input keyevent KEYCODE_WAKEUP");
         mUiDevice.executeShellCommand("wm dismiss-keyguard");