Remove unused variables

From aosp/537809, variables that used to fetch realtime
stats are defined in NetworkStatsService. These varialbles
are filled by JNI in boot up stage in order to keep
definitions sync with native layer.

However, there is still a copy in TrafficStats.java, and this
copy cannot be filled in boot-up stage since it is in app
process. Besides, making a binder call to fetch these
constants from service is considered an overkill.

Thus, since there is no caller to these variables and callers
should use definitions in TrafficStats, remove these variables.

Test: atest FrameworksNetTests
Bug: 16229221
Change-Id: I6a48d4dbb1b824cfc6c4a47395b2a76aa28cf5c9
diff --git a/services/core/java/com/android/server/net/NetworkStatsService.java b/services/core/java/com/android/server/net/NetworkStatsService.java
index bfd0211..81a6641 100644
--- a/services/core/java/com/android/server/net/NetworkStatsService.java
+++ b/services/core/java/com/android/server/net/NetworkStatsService.java
@@ -2214,15 +2214,6 @@
         }
     }
 
-    // TODO: Remove unused definitions after removing JNI that fills these variables.
-    //  See {@code com_android_server_net_NetworkStatsService.cpp}.
-    private static int TYPE_RX_BYTES;
-    private static int TYPE_RX_PACKETS;
-    private static int TYPE_TX_BYTES;
-    private static int TYPE_TX_PACKETS;
-    private static int TYPE_TCP_RX_PACKETS;
-    private static int TYPE_TCP_TX_PACKETS;
-
     private static native long nativeGetTotalStat(int type, boolean useBpfStats);
     private static native long nativeGetIfaceStat(String iface, int type, boolean useBpfStats);
     private static native long nativeGetUidStat(int uid, int type, boolean useBpfStats);
diff --git a/services/core/jni/com_android_server_net_NetworkStatsService.cpp b/services/core/jni/com_android_server_net_NetworkStatsService.cpp
index 0275f3e..10b248a 100644
--- a/services/core/jni/com_android_server_net_NetworkStatsService.cpp
+++ b/services/core/jni/com_android_server_net_NetworkStatsService.cpp
@@ -215,21 +215,6 @@
 };
 
 int register_android_server_net_NetworkStatsService(JNIEnv* env) {
-    jclass netStatsService = env->FindClass("com/android/server/net/NetworkStatsService");
-    jfieldID rxBytesId = env->GetStaticFieldID(netStatsService, "TYPE_RX_BYTES", "I");
-    jfieldID rxPacketsId = env->GetStaticFieldID(netStatsService, "TYPE_RX_PACKETS", "I");
-    jfieldID txBytesId = env->GetStaticFieldID(netStatsService, "TYPE_TX_BYTES", "I");
-    jfieldID txPacketsId = env->GetStaticFieldID(netStatsService, "TYPE_TX_PACKETS", "I");
-    jfieldID tcpRxPacketsId = env->GetStaticFieldID(netStatsService, "TYPE_TCP_RX_PACKETS", "I");
-    jfieldID tcpTxPacketsId = env->GetStaticFieldID(netStatsService, "TYPE_TCP_TX_PACKETS", "I");
-
-    env->SetStaticIntField(netStatsService, rxBytesId, RX_BYTES);
-    env->SetStaticIntField(netStatsService, rxPacketsId, RX_PACKETS);
-    env->SetStaticIntField(netStatsService, txBytesId, TX_BYTES);
-    env->SetStaticIntField(netStatsService, txPacketsId, TX_PACKETS);
-    env->SetStaticIntField(netStatsService, tcpRxPacketsId, TCP_RX_PACKETS);
-    env->SetStaticIntField(netStatsService, tcpTxPacketsId, TCP_TX_PACKETS);
-
     return jniRegisterNativeMethods(env, "com/android/server/net/NetworkStatsService", gMethods,
                                     NELEM(gMethods));
 }