diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/NetworkStatsUtilsTest.kt b/staticlibs/tests/unit/src/com/android/net/module/util/NetworkStatsUtilsTest.kt
index 2785ea9..baadad0 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/NetworkStatsUtilsTest.kt
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/NetworkStatsUtilsTest.kt
@@ -17,13 +17,13 @@
 package com.android.net.module.util
 
 import android.net.NetworkStats
-import android.text.TextUtils
 import androidx.test.filters.SmallTest
 import androidx.test.runner.AndroidJUnit4
-import org.junit.Test
-import org.junit.runner.RunWith
+import com.android.testutils.assertEntryEquals
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
+import org.junit.Test
+import org.junit.runner.RunWith
 import org.mockito.Mockito.doReturn
 import org.mockito.Mockito.mock
 
@@ -90,8 +90,6 @@
             NetworkStats.ROAMING_NO, NetworkStats.DEFAULT_NETWORK_ALL, 1024, 8, 2048, 12,
             0 /* operations */)
 
-        // TODO: Use assertEquals once all downstreams accept null iface in
-        // NetworkStats.Entry#equals.
         assertEntryEquals(expectedEntry, entry)
     }
 
@@ -121,22 +119,4 @@
         doReturn(txPackets).`when`(ret).getTxPackets()
         return ret
     }
-
-    /**
-     * Assert that the two {@link NetworkStats.Entry} are equals.
-     */
-    private fun assertEntryEquals(left: NetworkStats.Entry, right: NetworkStats.Entry) {
-        TextUtils.equals(left.iface, right.iface)
-        assertEquals(left.uid, right.uid)
-        assertEquals(left.set, right.set)
-        assertEquals(left.tag, right.tag)
-        assertEquals(left.metered, right.metered)
-        assertEquals(left.roaming, right.roaming)
-        assertEquals(left.defaultNetwork, right.defaultNetwork)
-        assertEquals(left.rxBytes, right.rxBytes)
-        assertEquals(left.rxPackets, right.rxPackets)
-        assertEquals(left.txBytes, right.txBytes)
-        assertEquals(left.txPackets, right.txPackets)
-        assertEquals(left.operations, right.operations)
-    }
 }
\ No newline at end of file
diff --git a/staticlibs/tests/unit/src/com/android/testutils/NetworkStatsUtilsTest.kt b/staticlibs/tests/unit/src/com/android/testutils/NetworkStatsUtilsTest.kt
index 2f436cd..57920fc 100644
--- a/staticlibs/tests/unit/src/com/android/testutils/NetworkStatsUtilsTest.kt
+++ b/staticlibs/tests/unit/src/com/android/testutils/NetworkStatsUtilsTest.kt
@@ -31,7 +31,7 @@
 import org.junit.runners.JUnit4
 
 private const val TEST_IFACE = "test0"
-private const val TEST_IFACE2 = "test2"
+private val TEST_IFACE2: String? = null
 private const val TEST_START = 1194220800000L
 
 @RunWith(JUnit4::class)
diff --git a/staticlibs/testutils/devicetests/com/android/testutils/NetworkStatsUtils.kt b/staticlibs/testutils/devicetests/com/android/testutils/NetworkStatsUtils.kt
index 8324b25..f2b14f5 100644
--- a/staticlibs/testutils/devicetests/com/android/testutils/NetworkStatsUtils.kt
+++ b/staticlibs/testutils/devicetests/com/android/testutils/NetworkStatsUtils.kt
@@ -17,7 +17,14 @@
 package com.android.testutils
 
 import android.net.NetworkStats
+import android.text.TextUtils
+import com.android.modules.utils.build.SdkLevel
 import kotlin.test.assertTrue
+import org.mockito.ArgumentMatchers.any
+import org.mockito.ArgumentMatchers.anyBoolean
+import org.mockito.ArgumentMatchers.anyInt
+import org.mockito.ArgumentMatchers.anyLong
+import org.mockito.Mockito
 
 @JvmOverloads
 fun orderInsensitiveEquals(
@@ -26,7 +33,7 @@
     compareTime: Boolean = false
 ): Boolean {
     if (leftStats == rightStats) return true
-    if (compareTime && leftStats.getElapsedRealtime() != rightStats.getElapsedRealtime()) {
+    if (compareTime && leftStats.elapsedRealtime != rightStats.elapsedRealtime) {
         return false
     }
 
@@ -47,12 +54,41 @@
                 left.metered, left.roaming, left.defaultNetwork, i)
         if (j == -1) return false
         rightTrimmedEmpty.getValues(j, right)
-        if (left != right) return false
+        if (SdkLevel.isAtLeastT()) {
+            if (left != right) return false
+        } else {
+            if (!checkEntryEquals(left, right)) return false
+        }
     }
     return true
 }
 
 /**
+ * Assert that the two {@link NetworkStats.Entry} are equals.
+ */
+fun assertEntryEquals(left: NetworkStats.Entry, right: NetworkStats.Entry) {
+    assertTrue(checkEntryEquals(left, right))
+}
+
+// TODO: Make all callers use NetworkStats.Entry#equals once S- downstreams
+//  are no longer supported. Because NetworkStats is mainlined on T+ and
+//  NetworkStats.Entry#equals in S- does not support null iface.
+fun checkEntryEquals(left: NetworkStats.Entry, right: NetworkStats.Entry): Boolean {
+    return TextUtils.equals(left.iface, right.iface) &&
+            left.uid == right.uid &&
+            left.set == right.set &&
+            left.tag == right.tag &&
+            left.metered == right.metered &&
+            left.roaming == right.roaming &&
+            left.defaultNetwork == right.defaultNetwork &&
+            left.rxBytes == right.rxBytes &&
+            left.rxPackets == right.rxPackets &&
+            left.txBytes == right.txBytes &&
+            left.txPackets == right.txPackets &&
+            left.operations == right.operations
+}
+
+/**
  * Assert that two {@link NetworkStats} are equals, assuming the order of the records are not
  * necessarily the same.
  *
@@ -66,7 +102,7 @@
     compareTime: Boolean = false
 ) {
     assertTrue(orderInsensitiveEquals(expected, actual, compareTime),
-            "expected: " + expected + " but was: " + actual)
+            "expected: $expected but was: $actual")
 }
 
 /**
@@ -74,5 +110,5 @@
  * object.
  */
 fun assertParcelingIsLossless(stats: NetworkStats) {
-    assertParcelingIsLossless(stats, { a, b -> orderInsensitiveEquals(a, b) })
+    assertParcelingIsLossless(stats) { a, b -> orderInsensitiveEquals(a, b) }
 }