Create Double Tap Power Settings Activity

Test: manually launched activity
Bug: 390257067
Flag: EXEMPT declared activity in xml
Change-Id: Idc858b4e916df7e716790b7297b1bd5a58874452

src/com/android/settings/Settings.java

@@ -518,6 +518,11 @@ public class Settings extends SettingsActivity {
      */
     public static class OneHandedSettingsActivity extends SettingsActivity { /* empty */ }
 
+    /**
+     * Activity for Double Tap Power Settings
+     */
+    public static class DoubleTapPowerSettingsActivity extends SettingsActivity { /* empty */ }
+
     public static class PreviouslyConnectedDeviceActivity extends SettingsActivity { /* empty */ }
 
     public static class ScreenTimeoutActivity extends SettingsActivity { /* empty */ }