Add resolvePkgPrefix() method

This is a no-op refactor change to create resolvePkgPrefix()
helper method to prevent code duplication for the follow up
commit.

Bug: 291870956
Test: atest NetworkStaticLibTests
Change-Id: I8deea97acdb793dfa076ce55f7f2c3eb0b224461
diff --git a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
index 138c1e5..e5c5d0d 100644
--- a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
+++ b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
@@ -224,14 +224,7 @@
     // If that fails retry by appending "go.tethering" instead
     private static long resolveTetheringModuleVersion(@NonNull Context context)
             throws PackageManager.NameNotFoundException {
-        final String connResourcesPackage = getConnectivityResourcesPackageName(context);
-        final int pkgPrefixLen = connResourcesPackage.indexOf("connectivity");
-        if (pkgPrefixLen < 0) {
-            throw new IllegalStateException(
-                    "Invalid connectivity resources package: " + connResourcesPackage);
-        }
-
-        final String pkgPrefix = connResourcesPackage.substring(0, pkgPrefixLen);
+        final String pkgPrefix = resolvePkgPrefix(context);
         final PackageManager packageManager = context.getPackageManager();
         try {
             return packageManager.getPackageInfo(pkgPrefix + "tethering",
@@ -245,6 +238,17 @@
                 PackageManager.MATCH_APEX).getLongVersionCode();
     }
 
+    private static String resolvePkgPrefix(Context context) {
+        final String connResourcesPackage = getConnectivityResourcesPackageName(context);
+        final int pkgPrefixLen = connResourcesPackage.indexOf("connectivity");
+        if (pkgPrefixLen < 0) {
+            throw new IllegalStateException(
+                    "Invalid connectivity resources package: " + connResourcesPackage);
+        }
+
+        return connResourcesPackage.substring(0, pkgPrefixLen);
+    }
+
     private static volatile long sModuleVersion = -1;
     private static long getTetheringModuleVersion(@NonNull Context context) {
         if (sModuleVersion >= 0) return sModuleVersion;