Remove unused mOpenSessionCallsPerUid from NetworkStatsService

mOpenSessionCallsPerUid can be removed since it is actually unused
in current design.

Bug: 237368619
Test: FrameworksNetTests
Change-Id: Idad646d6901a40dddc7d9cb85dd2227179180755
diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
index b08879e..52c168b 100644
--- a/service-t/src/com/android/server/net/NetworkStatsService.java
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -427,12 +427,7 @@
     private long mLastStatsSessionPoll;
 
     private final Object mOpenSessionCallsLock = new Object();
-    /**
-     * Map from UID to number of opened sessions. This is used for rate-limt an app to open
-     * session frequently
-     */
-    @GuardedBy("mOpenSessionCallsLock")
-    private final SparseIntArray mOpenSessionCallsPerUid = new SparseIntArray();
+
     /**
      * Map from key {@code OpenSessionKey} to count of opened sessions. This is for recording
      * the caller of open session and it is only for debugging.
@@ -1321,9 +1316,6 @@
                 mOpenSessionCallsPerCaller.put(key, Integer.sum(callsPerCaller, 1));
             }
 
-            int callsPerUid = mOpenSessionCallsPerUid.get(key.uid, 0);
-            mOpenSessionCallsPerUid.put(key.uid, callsPerUid + 1);
-
             if (key.uid == android.os.Process.SYSTEM_UID) {
                 return false;
             }
@@ -2474,8 +2466,7 @@
         for (int uid : uids) {
             deleteKernelTagData(uid);
         }
-        // TODO: Remove the UID's entries from mOpenSessionCallsPerUid and
-        // mOpenSessionCallsPerCaller
+        // TODO: Remove the UID's entries from mOpenSessionCallsPerCaller.
     }
 
     /**