Add network logging icon to Quicksettings when enabled

Add the network logging icon in Quick Settings' footer if
network logging is enabled, possible next to the VPN icon.
Quicksettings has to be able to tell that network logging
is enabled, so this CL changes DPM.isNetworkLoggingEnabled() to be
callable from the device owner or from any app with the MANAGE_USERS
permission.

The icon is only a placeholder until the official icon is finished.

CTS Verifier tests will be added when all Network logging UX changes are
done.

BUG: 33126618
BUG: 29748723
Test: runtest --path frameworks/base/packages/SystemUI/tests
Change-Id: Ib35d323605ab11f883a4b6199d1db79b9e53c49b
diff --git a/core/java/android/app/admin/DevicePolicyManager.java b/core/java/android/app/admin/DevicePolicyManager.java
index ce10bad..39f415e 100644
--- a/core/java/android/app/admin/DevicePolicyManager.java
+++ b/core/java/android/app/admin/DevicePolicyManager.java
@@ -6939,11 +6939,13 @@
     /**
      * Return whether network logging is enabled by a device owner.
      *
-     * @param admin Which {@link DeviceAdminReceiver} this request is associated with.
+     * @param admin Which {@link DeviceAdminReceiver} this request is associated with. Can only
+     * be {@code null} if the caller has MANAGE_USERS permission.
      * @return {@code true} if network logging is enabled by device owner, {@code false} otherwise.
-     * @throws {@link SecurityException} if {@code admin} is not a device owner.
+     * @throws {@link SecurityException} if {@code admin} is not a device owner and caller has
+     * no MANAGE_USERS permission
      */
-    public boolean isNetworkLoggingEnabled(@NonNull ComponentName admin) {
+    public boolean isNetworkLoggingEnabled(@Nullable ComponentName admin) {
         throwIfParentInstance("isNetworkLoggingEnabled");
         try {
             return mService.isNetworkLoggingEnabled(admin);