Hide dev options v1 under feature flag

 - Cutover to DevelopmentSettingsDashboardFragment
 - Add dev_option_v1 feature flag

Bug: 34203528
Test: make RunSettingsRoboTests -j40
Change-Id: I2ff7b5c55f1f27cd24b4e276d3d81a73f67dcf88
diff --git a/src/com/android/settings/Settings.java b/src/com/android/settings/Settings.java
index 2377ca5..eac3801 100644
--- a/src/com/android/settings/Settings.java
+++ b/src/com/android/settings/Settings.java
@@ -73,12 +73,12 @@
      * @deprecated in favor of {@link DevelopmentSettingsDashboardActivity}.
      */
     @Deprecated
-    public static class DevelopmentSettingsActivity extends SettingsActivity { /* empty */ }
-    public static class DevelopmentSettingsDashboardActivity extends SettingsActivity {
+    public static class DevelopmentSettingsActivity extends SettingsActivity {
         public static final boolean isEnabled() {
-            return FeatureFlagUtils.isEnabled("dev_option_v2");
+            return FeatureFlagUtils.isEnabled("dev_option_v1");
         }
     }
+    public static class DevelopmentSettingsDashboardActivity extends SettingsActivity { /* empty */ }
     public static class AccessibilitySettingsActivity extends SettingsActivity { /* empty */ }
     public static class CaptioningSettingsActivity extends SettingsActivity { /* empty */ }
     public static class AccessibilityInversionSettingsActivity extends SettingsActivity { /* empty */ }