Disable fallback when comparison result is different

Follow-up from ag/18452103, where we add fallback code that runs
with the importer to make sure they are identical.
When the result is different, we'll take the result from fallback
code to minimize the rollout risk. However, since the OEMs might
change the importer implementation. The fallback code would no
longer valid and that makes OEM modified code not working. Hence
the fallback code must be disabled before release.

This change keeps comparison enabled for all cases to keep getting
signals from beta users. And will switch it to read overlay value
for OEM to debug their solution.

Test: 1. NetworkStatsServiceTest
      2. Test all datasets with script
Bug: 233752318
Change-Id: I869ff05297149bde6e13a204bd8c5a4fece75de0
Merged-In: I869ff05297149bde6e13a204bd8c5a4fece75de0
  (cherry-picked from ag/18849946)
diff --git a/service/ServiceConnectivityResources/res/values/config.xml b/service/ServiceConnectivityResources/res/values/config.xml
index 81782f9..bff6953 100644
--- a/service/ServiceConnectivityResources/res/values/config.xml
+++ b/service/ServiceConnectivityResources/res/values/config.xml
@@ -179,4 +179,13 @@
     Only supported up to S. On T+, the Wi-Fi code should use unregisterAfterReplacement in order
     to ensure that apps see the network disconnect and reconnect. -->
     <integer translatable="false" name="config_validationFailureAfterRoamIgnoreTimeMillis">-1</integer>
+
+    <!-- Whether the network stats service should run compare on the result of
+    {@link NetworkStatsDataMigrationUtils#readPlatformCollection} and the result
+    of reading from legacy recorders. Possible values are:
+      0 = never compare,
+      1 = always compare,
+      2 = compare on debuggable builds (default value)
+      -->
+    <integer translatable="false" name="config_netstats_validate_import">2</integer>
 </resources>