ToolsInstallerPreference: Examine current state on load

Signed-off-by: Samuel Holland <samuel@sholland.org>

app/src/main/java/com/wireguard/android/preference/ToolsInstallerPreference.java

@@ -58,6 +58,13 @@ public class ToolsInstallerPreference extends Preference {
         return R.string.tools_installer_title;
     }
 
+    @Override
+    protected void onAttachedToActivity() {
+        super.onAttachedToActivity();
+        asyncWorker.supplyAsync(toolsInstaller::areInstalled)
+                .thenAccept(installed -> setState(installed ? State.ALREADY : State.INITIAL));
+    }
+
     @Override
     protected void onClick() {
         setState(State.WORKING);