Add a developer option to enable / disable location indicators.

Also bundled location related developer options into the location
category.

Bug:175357420

Test: Manual && make RunSettingsRoboTests ROBOTEST_FILTER=LocationScanningPreferenceControllerTest

Change-Id: Ic33ad6e70d258c9afc2cefba70ab6e7b2bafd16a
diff --git a/src/com/android/settings/Utils.java b/src/com/android/settings/Utils.java
index b6a9f59..4390aad 100644
--- a/src/com/android/settings/Utils.java
+++ b/src/com/android/settings/Utils.java
@@ -143,6 +143,11 @@
     public static final String PROPERTY_PERMISSIONS_HUB_ENABLED = "permissions_hub_enabled";
 
     /**
+     * Whether to show location indicators.
+     */
+    public static final String PROPERTY_LOCATION_INDICATORS_ENABLED = "location_indicators_enabled";
+
+    /**
      * Finds a matching activity for a preference's intent. If a matching
      * activity is not found, it will remove the preference.
      *