IMS: Add support in frameworks for call deflection feature

Call deflection feature is useful to deflect MT call to another
number.

Test: Manual

Bug: 62170348
Change-Id: Idfbcc175a856aa0bb9476f8c73d7a614a3af0700
diff --git a/telephony/java/android/telephony/CarrierConfigManager.java b/telephony/java/android/telephony/CarrierConfigManager.java
index 046b8be..f360680 100644
--- a/telephony/java/android/telephony/CarrierConfigManager.java
+++ b/telephony/java/android/telephony/CarrierConfigManager.java
@@ -1370,6 +1370,12 @@
      */
     public static final String KEY_ALLOW_HOLD_IN_IMS_CALL_BOOL = "allow_hold_in_ims_call";
 
+    /**
+     * Flag indicating whether the carrier supports call deflection for an incoming IMS call.
+     * @hide
+     */
+    public static final String KEY_CARRIER_ALLOW_DEFLECT_IMS_CALL_BOOL =
+            "carrier_allow_deflect_ims_call_bool";
 
     /**
      * Flag indicating whether the carrier always wants to play an "on-hold" tone when a call has
@@ -1822,6 +1828,7 @@
     static {
         sDefaults = new PersistableBundle();
         sDefaults.putBoolean(KEY_ALLOW_HOLD_IN_IMS_CALL_BOOL, true);
+        sDefaults.putBoolean(KEY_CARRIER_ALLOW_DEFLECT_IMS_CALL_BOOL, false);
         sDefaults.putBoolean(KEY_ALWAYS_PLAY_REMOTE_HOLD_TONE_BOOL, false);
         sDefaults.putBoolean(KEY_ADDITIONAL_CALL_SETTING_BOOL, true);
         sDefaults.putBoolean(KEY_ALLOW_EMERGENCY_NUMBERS_IN_CALL_LOG_BOOL, false);