Remove injecting developer options into Settings itself

- It can improve performance because we use less injected item
- Also use RestrictedPreference instead just checking restrictions,
  so we follow policy transparency.

Note: Renamed DevelopmentSettingsDashboardActivity to
DevelopmentSettingsActivity,
because DevelopmentSettingsDashboardActivity could in disabled state
even after Settings upgrades, use a new name to prevent this issue.

Bug: 311604902
Test: manual - turn on / off Developer Options
Test: unit test
Change-Id: I17be117ae59e59410687e6d08fd5edd034d0508f

src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java

@@ -47,6 +47,7 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.CompoundButton;
 import android.widget.CompoundButton.OnCheckedChangeListener;
+import android.widget.Toast;
 
 import androidx.annotation.VisibleForTesting;
 import androidx.localbroadcastmanager.content.LocalBroadcastManager;
@@ -230,6 +231,12 @@ public class DevelopmentSettingsDashboardFragment extends RestrictedDashboardFra
             getActivity().finish();
             return;
         }
+        Context context = requireContext();
+        if (!DevelopmentSettingsEnabler.isDevelopmentSettingsEnabled(context)) {
+            Toast.makeText(context, R.string.dev_settings_disabled_warning, Toast.LENGTH_SHORT)
+                    .show();
+            finish();
+        }
     }
 
     @Override