[DU04-4]Appropriate changes to the NetworkPolicyManager API

Divide the NetworkPolicyManager API
notifyStatsProviderWarningOrLimitReached into the following two APIs:
1. notifyStatsProviderWarningReached()
2. notifyStatsProviderLimitReached()

Bug: 216474563
Test: atest NetworkStatsServiceTest NetworkPolicyManagerTest
            NetworkPolicyManagerServiceTest OffloadControllerTest
Change-Id: I473b8b677d492a7076e63f445b3a3be24d25e14d
diff --git a/Tethering/tests/unit/src/com/android/networkstack/tethering/OffloadControllerTest.java b/Tethering/tests/unit/src/com/android/networkstack/tethering/OffloadControllerTest.java
index fc34585..e9716b3 100644
--- a/Tethering/tests/unit/src/com/android/networkstack/tethering/OffloadControllerTest.java
+++ b/Tethering/tests/unit/src/com/android/networkstack/tethering/OffloadControllerTest.java
@@ -26,7 +26,7 @@
 import static android.net.RouteInfo.RTN_UNICAST;
 import static android.provider.Settings.Global.TETHER_OFFLOAD_DISABLED;
 
-import static com.android.modules.utils.build.SdkLevel.isAtLeastS;
+import static com.android.modules.utils.build.SdkLevel.isAtLeastT;
 import static com.android.networkstack.tethering.OffloadController.StatsType.STATS_PER_IFACE;
 import static com.android.networkstack.tethering.OffloadController.StatsType.STATS_PER_UID;
 import static com.android.networkstack.tethering.OffloadHardwareInterface.ForwardedStats;
@@ -666,10 +666,12 @@
         callback.onStoppedLimitReached();
         mTetherStatsProviderCb.expectNotifyStatsUpdated();
 
-        if (isAtLeastS()) {
+        if (isAtLeastT()) {
+            mTetherStatsProviderCb.expectNotifyLimitReached();
+        } else if (Build.VERSION.SDK_INT == Build.VERSION_CODES.S) {
             mTetherStatsProviderCb.expectNotifyWarningOrLimitReached();
         } else {
-            mTetherStatsProviderCb.expectLegacyNotifyLimitReached();
+            mTetherStatsProviderCb.expectNotifyLimitReached();
         }
     }
 
@@ -680,7 +682,12 @@
         final OffloadHardwareInterface.ControlCallback callback = mControlCallbackCaptor.getValue();
         callback.onWarningReached();
         mTetherStatsProviderCb.expectNotifyStatsUpdated();
-        mTetherStatsProviderCb.expectNotifyWarningOrLimitReached();
+
+        if (isAtLeastT()) {
+            mTetherStatsProviderCb.expectNotifyWarningReached();
+        } else {
+            mTetherStatsProviderCb.expectNotifyWarningOrLimitReached();
+        }
     }
 
     @Test