[BR14] Tracker Data Saver status in ConnectivityService

BYPASS_INCLUSIVE_LANGUAGE_REASON=Using public API
Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.CSBpfNetMapsTest
      (on U and V devices respectively)
Bug: 297836825
Fix: 314858283

Change-Id: Ibeac8cd3a33468c6539234255328affc6b3f8ffe

tests/unit/java/com/android/server/connectivityservice/CSBpfNetMapsTest.kt

@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server
+
+import android.content.Intent
+import android.net.ConnectivityManager.ACTION_RESTRICT_BACKGROUND_CHANGED
+import android.net.ConnectivityManager.RESTRICT_BACKGROUND_STATUS_DISABLED
+import android.net.ConnectivityManager.RESTRICT_BACKGROUND_STATUS_ENABLED
+import android.net.ConnectivityManager.RESTRICT_BACKGROUND_STATUS_WHITELISTED
+import android.os.Build
+import androidx.test.filters.SmallTest
+import com.android.testutils.DevSdkIgnoreRule
+import com.android.testutils.DevSdkIgnoreRule.IgnoreAfter
+import com.android.testutils.DevSdkIgnoreRule.IgnoreUpTo
+import com.android.testutils.DevSdkIgnoreRunner
+import com.android.testutils.visibleOnHandlerThread
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.ArgumentMatchers.anyBoolean
+import org.mockito.ArgumentMatchers.anyInt
+import org.mockito.Mockito.doReturn
+import org.mockito.Mockito.inOrder
+import org.mockito.Mockito.never
+import org.mockito.Mockito.verify
+
+@RunWith(DevSdkIgnoreRunner::class)
+@SmallTest
+@IgnoreUpTo(Build.VERSION_CODES.S_V2) // Bpf only supports in T+.
+class CSBpfNetMapsTest : CSTest() {
+    @get:Rule
+    val ignoreRule = DevSdkIgnoreRule()
+
+    @IgnoreAfter(Build.VERSION_CODES.UPSIDE_DOWN_CAKE)
+    @Test
+    fun testCSTrackDataSaverBeforeV() {
+        val inOrder = inOrder(bpfNetMaps)
+        mockDataSaverStatus(RESTRICT_BACKGROUND_STATUS_WHITELISTED)
+        inOrder.verify(bpfNetMaps).setDataSaverEnabled(true)
+        mockDataSaverStatus(RESTRICT_BACKGROUND_STATUS_DISABLED)
+        inOrder.verify(bpfNetMaps).setDataSaverEnabled(false)
+        mockDataSaverStatus(RESTRICT_BACKGROUND_STATUS_ENABLED)
+        inOrder.verify(bpfNetMaps).setDataSaverEnabled(true)
+    }
+
+    // Data Saver Status is updated from platform code in V+.
+    @IgnoreUpTo(Build.VERSION_CODES.UPSIDE_DOWN_CAKE)
+    @Test
+    fun testCSTrackDataSaverAboveU() {
+        listOf(RESTRICT_BACKGROUND_STATUS_WHITELISTED, RESTRICT_BACKGROUND_STATUS_ENABLED,
+            RESTRICT_BACKGROUND_STATUS_DISABLED).forEach {
+            mockDataSaverStatus(it)
+            verify(bpfNetMaps, never()).setDataSaverEnabled(anyBoolean())
+        }
+    }
+
+    private fun mockDataSaverStatus(status: Int) {
+        doReturn(status).`when`(context.networkPolicyManager).getRestrictBackgroundStatus(anyInt())
+        // While the production code dispatches the intent on the handler thread,
+        // The test would dispatch the intent in the caller thread. Make it dispatch
+        // on the handler thread to match production behavior.
+        visibleOnHandlerThread(csHandler) {
+            context.sendBroadcast(Intent(ACTION_RESTRICT_BACKGROUND_CHANGED))
+        }
+        waitForIdle()
+    }
+}