Permit deactivation of malformed Device Admins.

Bug: 9074296
Change-Id: I4a3b2f972cb297b9f985a762219c8d67d8e3a425

src/com/android/settings/DeviceAdminAdd.java

@@ -116,7 +116,10 @@ public class DeviceAdminAdd extends Activity {
             return;
         }
 
-        // Make sure the given component name is actually a valid device admin.
+        // When activating, make sure the given component name is actually a valid device admin.
+        // No need to check this when deactivating, because it is safe to deactivate an active
+        // invalid device admin.
+        if (!mDPM.isAdminActive(cn)) {
             List<ResolveInfo> avail = getPackageManager().queryBroadcastReceivers(
                     new Intent(DeviceAdminReceiver.ACTION_DEVICE_ADMIN_ENABLED),
                     0);
@@ -145,6 +148,7 @@ public class DeviceAdminAdd extends Activity {
                 finish();
                 return;
             }
+        }
 
         ResolveInfo ri = new ResolveInfo();
         ri.activityInfo = ai;