RTT initialization bug fixes

Add a setting toggle to enable/disable RTT
Allow calls to be initiated with RTT enabled (add plumbing)
Refactor to match the change to dial()

Bug: 71873552
Test: manual
Change-Id: I79b415751b7f1495a3cd603b83f8c4df4389c4c8
Merged-In: I79b415751b7f1495a3cd603b83f8c4df4389c4c8
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index f10a609..cb45eb0 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -3265,6 +3265,14 @@
         return mPhone.getContext().getResources().getBoolean(R.bool.hac_enabled);
     }
 
+    public boolean isRttSupported() {
+        boolean isCarrierSupported =
+                mApp.getCarrierConfig().getBoolean(CarrierConfigManager.KEY_RTT_SUPPORTED_BOOL);
+        boolean isDeviceSupported =
+                mPhone.getContext().getResources().getBoolean(R.bool.config_support_rtt);
+        return isCarrierSupported && isDeviceSupported;
+    }
+
     /**
      * Returns the unique device ID of phone, for example, the IMEI for
      * GSM and the MEID for CDMA phones. Return null if device ID is not available.