Fixed that telephony registry service reference incorrectly assigned

The reference to telephony registry service was assigned
prior telephony registry service was ready. Fixed by
casting the binder every time when we use it.

Test: Manual
Bug: 65593241
Merged-In: Ib234cdfd93130f7af44ef79271b106fffb8ebad5
Change-Id: Ib234cdfd93130f7af44ef79271b106fffb8ebad5
(cherry picked from commit 66420e258a)

telephony/java/android/telephony/TelephonyManager.java

@@ -106,8 +106,6 @@ public class TelephonyManager {
     public static final String MODEM_ACTIVITY_RESULT_KEY =
             BatteryStats.RESULT_RECEIVER_CONTROLLER_KEY;
 
-    private static ITelephonyRegistry sRegistry;
-
     /**
      * The allowed states of Wi-Fi calling.
      *
@@ -178,11 +176,6 @@ public class TelephonyManager {
             mContext = context;
         }
         mSubscriptionManager = SubscriptionManager.from(mContext);
-
-        if (sRegistry == null) {
-            sRegistry = ITelephonyRegistry.Stub.asInterface(ServiceManager.getService(
-                    "telephony.registry"));
-        }
     }
 
     /** @hide */
@@ -3453,6 +3446,10 @@ public class TelephonyManager {
         return ITelecomService.Stub.asInterface(ServiceManager.getService(Context.TELECOM_SERVICE));
     }
 
+    private ITelephonyRegistry getTelephonyRegistry() {
+        return ITelephonyRegistry.Stub.asInterface(ServiceManager.getService("telephony.registry"));
+    }
+
     //
     //
     // PhoneStateListener
@@ -3492,12 +3489,16 @@ public class TelephonyManager {
             if (listener.mSubId == null) {
                 listener.mSubId = mSubId;
             }
-            sRegistry.listenForSubscriber(listener.mSubId, getOpPackageName(),
-                    listener.callback, events, notifyNow);
+
+            ITelephonyRegistry registry = getTelephonyRegistry();
+            if (registry != null) {
+                registry.listenForSubscriber(listener.mSubId, getOpPackageName(),
+                        listener.callback, events, notifyNow);
+            } else {
+                Rlog.w(TAG, "telephony registry not ready.");
+            }
         } catch (RemoteException ex) {
             // system process dead
-        } catch (NullPointerException ex) {
-            // system process dead
         }
     }