Remove useless methods from NetworkStatsRecorder

In order to increase the line coverage for the Connectivity
module, remove the useless methods from NetworkStatsRecorder.

Bug: 234315786
Test: atest FrameworksNetTests CtsNetTestCases \
      ConnectivityCoverageTest
Change-Id: I6ef08d220ad69ec3c945dd54be1b51814d2438b2
diff --git a/service-t/src/com/android/server/net/NetworkStatsRecorder.java b/service-t/src/com/android/server/net/NetworkStatsRecorder.java
index d73e342..d99e164 100644
--- a/service-t/src/com/android/server/net/NetworkStatsRecorder.java
+++ b/service-t/src/com/android/server/net/NetworkStatsRecorder.java
@@ -43,7 +43,6 @@
 import libcore.io.IoUtils;
 
 import java.io.ByteArrayOutputStream;
-import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -423,46 +422,6 @@
         }
     }
 
-    public void importLegacyNetworkLocked(File file) throws IOException {
-        Objects.requireNonNull(mRotator, "missing FileRotator");
-
-        // legacy file still exists; start empty to avoid double importing
-        mRotator.deleteAll();
-
-        final NetworkStatsCollection collection = new NetworkStatsCollection(mBucketDuration);
-        collection.readLegacyNetwork(file);
-
-        final long startMillis = collection.getStartMillis();
-        final long endMillis = collection.getEndMillis();
-
-        if (!collection.isEmpty()) {
-            // process legacy data, creating active file at starting time, then
-            // using end time to possibly trigger rotation.
-            mRotator.rewriteActive(new CombiningRewriter(collection), startMillis);
-            mRotator.maybeRotate(endMillis);
-        }
-    }
-
-    public void importLegacyUidLocked(File file) throws IOException {
-        Objects.requireNonNull(mRotator, "missing FileRotator");
-
-        // legacy file still exists; start empty to avoid double importing
-        mRotator.deleteAll();
-
-        final NetworkStatsCollection collection = new NetworkStatsCollection(mBucketDuration);
-        collection.readLegacyUid(file, mOnlyTags);
-
-        final long startMillis = collection.getStartMillis();
-        final long endMillis = collection.getEndMillis();
-
-        if (!collection.isEmpty()) {
-            // process legacy data, creating active file at starting time, then
-            // using end time to possibly trigger rotation.
-            mRotator.rewriteActive(new CombiningRewriter(collection), startMillis);
-            mRotator.maybeRotate(endMillis);
-        }
-    }
-
     /**
      * Import a specified {@link NetworkStatsCollection} instance into this recorder,
      * and write it into a standalone file.