FPII-2924 :[Part 2]Elevation of privilege vulnerability in Telephony CVE-2017-0554 A-33815946

Added permission check for setCellInfoListRate

Now the caller needs to have MODIFY_PHONE_STATE to call
this API.

Test: Manual
bug: 33815946
Change-Id: Ia2cf0de383572033c70b94ae71080ef35c3f443c
(cherry picked from commit 3128d9ec40fadccbf2be7b9e962e35b9bfbc003a)
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 2b8c34d..c1b2839 100755
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -1336,6 +1336,7 @@
 
     @Override
     public void setCellInfoListRate(int rateInMillis) {
+        enforceModifyPermission();
         mPhone.setCellInfoListRate(rateInMillis);
     }