Add debug flag for App Settings page

Default no-op, if SETTINGS_ENABLE_SPA is enabled, InstalledAppDetailsTop
will navigate to SPA AppSettings instead of AppInfoDashboardFragment.

Bug: 236346018
Test: Manual with Settings App
Change-Id: I0b8a668df1f8783b860baae1d912157f742baf3f

src/com/android/settings/applications/InstalledAppDetailsTop.java

@@ -17,12 +17,28 @@
 package com.android.settings.applications;
 
 import android.content.Intent;
+import android.os.Bundle;
+import android.util.FeatureFlagUtils;
 
 import com.android.settings.SettingsActivity;
 import com.android.settings.applications.appinfo.AppInfoDashboardFragment;
+import com.android.settings.spa.SpaActivity;
+import com.android.settings.spa.app.appsettings.AppSettingsProvider;
 
 public class InstalledAppDetailsTop extends SettingsActivity {
 
+    @Override
+    protected void onCreate(Bundle savedState) {
+        super.onCreate(savedState);
+        if (!FeatureFlagUtils.isEnabled(this, FeatureFlagUtils.SETTINGS_ENABLE_SPA)) {
+            return;
+        }
+        String packageName = super.getIntent().getData().getSchemeSpecificPart();
+        SpaActivity.startSpaActivity(
+                this, AppSettingsProvider.INSTANCE.getRoute(packageName, getUserId()));
+        finish();
+    }
+
     @Override
     public Intent getIntent() {
         Intent modIntent = new Intent(super.getIntent());

src/com/android/settings/spa/app/appsettings/AppSettings.kt

@@ -60,6 +60,13 @@ object AppSettingsProvider : SettingsPageProvider {
 
     @Composable
     fun navigator(app: ApplicationInfo) = navigator(route = "$name/${app.toRoute()}")
+
+    /**
+     * Gets the route to the App Settings page.
+     *
+     * Expose route to enable enter from non-SPA pages.
+     */
+    fun getRoute(packageName: String, userId: Int): String = "$name/$packageName/$userId"
 }
 
 @Composable