Unexpose getDataRoamingFromRegistration API

Test: build
Bug: 148604865
Change-Id: I695645418d2babc1eb524a29b2054c1cd8f74da3
diff --git a/api/system-current.txt b/api/system-current.txt
index bfdb052..fe9f37d 100755
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -11368,7 +11368,6 @@
     method public void fillInNotifierBundle(@NonNull android.os.Bundle);
     method public int getDataNetworkType();
     method public int getDataRegistrationState();
-    method public boolean getDataRoamingFromRegistration();
     method @Nullable public android.telephony.NetworkRegistrationInfo getNetworkRegistrationInfo(int, int);
     method @NonNull public java.util.List<android.telephony.NetworkRegistrationInfo> getNetworkRegistrationInfoListForDomain(int);
     method @NonNull public java.util.List<android.telephony.NetworkRegistrationInfo> getNetworkRegistrationInfoListForTransportType(int);
diff --git a/telephony/java/android/telephony/ServiceState.java b/telephony/java/android/telephony/ServiceState.java
index 9b1baef..906c390 100644
--- a/telephony/java/android/telephony/ServiceState.java
+++ b/telephony/java/android/telephony/ServiceState.java
@@ -689,8 +689,9 @@
      * @return true if registration indicates roaming, false otherwise
      * @hide
      */
-    @SystemApi
     public boolean getDataRoamingFromRegistration() {
+        // TODO: all callers should refactor to get roaming state directly from modem
+        // this should not be exposed as a public API
         return mIsDataRoamingFromRegistration;
     }