Add back increasing ring feature (2/3).

Change-Id: Ie21e09f923001cfbab5a611426516a2a4ec23ac1
Signed-off-by: Mohammad Hasan Keramat J <ikeramat@protonmail.com>

core/java/android/provider/Settings.java

@@ -5679,6 +5679,22 @@ public final class Settings {
         public static final String STATUS_BAR_SHOW_BATTERY_PERCENT =
                 "status_bar_battery_percent";
+        /**
+         * Whether the phone ringtone should be played in an increasing manner
+         * @hide
+         */
+        public static final String INCREASING_RING = "increasing_ring";
+        /**
+         * Start volume fraction for increasing ring volume
+         * @hide
+         */
+        public static final String INCREASING_RING_START_VOLUME = "increasing_ring_start_vol";
+        /**
+         * Ramp up time (seconds) for increasing ring
+         * @hide
+         */
+        public static final String INCREASING_RING_RAMP_UP_TIME = "increasing_ring_ramp_up_time";
+
         /**
          * IMPORTANT: If you add a new public settings you also have to add it to
          * PUBLIC_SETTINGS below. If the new setting is hidden you have to add