Move IoUtils#deleteContents from CorePlatformApi set to framework

As a part of internal core libraries cleanup move usages of
IoUtils#deleteContents from CorePlatformApi set to framework.

Bug: 154796679
Test: m update-api
Change-Id: If7037029026b6753ab64be09aa52c40e04d5c7b1
diff --git a/tests/unit/java/com/android/server/net/NetworkStatsFactoryTest.java b/tests/unit/java/com/android/server/net/NetworkStatsFactoryTest.java
index f3ae9b0..93599f3 100644
--- a/tests/unit/java/com/android/server/net/NetworkStatsFactoryTest.java
+++ b/tests/unit/java/com/android/server/net/NetworkStatsFactoryTest.java
@@ -43,6 +43,7 @@
 import androidx.test.runner.AndroidJUnit4;
 
 import com.android.frameworks.tests.net.R;
+import com.android.internal.util.test.FsUtil;
 
 import libcore.io.IoUtils;
 import libcore.io.Streams;
@@ -71,7 +72,7 @@
     public void setUp() throws Exception {
         mTestProc = new File(InstrumentationRegistry.getContext().getFilesDir(), "proc");
         if (mTestProc.exists()) {
-            IoUtils.deleteContents(mTestProc);
+            FsUtil.deleteContents(mTestProc);
         }
 
         // The libandroid_servers which have the native method is not available to
@@ -87,7 +88,7 @@
         mFactory = null;
 
         if (mTestProc.exists()) {
-            IoUtils.deleteContents(mTestProc);
+            FsUtil.deleteContents(mTestProc);
         }
     }
 
diff --git a/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java b/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
index fd374bc..95ab322 100644
--- a/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
+++ b/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
@@ -112,13 +112,12 @@
 
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.test.BroadcastInterceptingContext;
+import com.android.internal.util.test.FsUtil;
 import com.android.server.net.NetworkStatsService.NetworkStatsSettings;
 import com.android.server.net.NetworkStatsService.NetworkStatsSettings.Config;
 import com.android.testutils.HandlerUtils;
 import com.android.testutils.TestableNetworkStatsProviderBinder;
 
-import libcore.io.IoUtils;
-
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Ignore;
@@ -213,7 +212,7 @@
         mServiceContext = new MockContext(context);
         mStatsDir = context.getFilesDir();
         if (mStatsDir.exists()) {
-            IoUtils.deleteContents(mStatsDir);
+            FsUtil.deleteContents(mStatsDir);
         }
 
         PowerManager powerManager = (PowerManager) mServiceContext.getSystemService(
@@ -283,7 +282,7 @@
 
     @After
     public void tearDown() throws Exception {
-        IoUtils.deleteContents(mStatsDir);
+        FsUtil.deleteContents(mStatsDir);
 
         mServiceContext = null;
         mStatsDir = null;