Remove usage of Math.randomLongInternal

As a part of internal libcore API cleanup some of the functions
previously exposed are getting removed from public surface.
Math#randomLongInternal is a wrapper around java.util.Random and has no
specific implications so its usages are get refactored.

Bug: 154796679
Test: m droid
Change-Id: I8db2400df0453baaddea6ab985f8e08a6338cfe0

services/core/java/com/android/server/pm/PackageDexOptimizer.java

@@ -80,6 +80,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
+import java.util.Random;
 
 /**
  * Helper class for running dexopt command on packages.
@@ -104,6 +105,8 @@ public class PackageDexOptimizer {
 
     private final ArtStatsLogger mArtStatsLogger = new ArtStatsLogger();
 
+    private static final Random sRandom = new Random();
+
     PackageDexOptimizer(Installer installer, Object installLock, Context context,
             String wakeLockTag) {
         this.mInstaller = installer;
@@ -262,7 +265,7 @@ public class PackageDexOptimizer {
                 if (packageStats != null) {
                     Trace.traceBegin(Trace.TRACE_TAG_PACKAGE_MANAGER, "dex2oat-metrics");
                     try {
-                        long sessionId = Math.randomLongInternal();
+                        long sessionId = sRandom.nextLong();
                         ArtStatsLogUtils.writeStatsLog(
                                 mArtStatsLogger,
                                 sessionId,