Revert "Use SequentialStoredFieldsLeafReader to read Lucene changes (#67190)" (#68586)

This reverts commit 5fe0d67ade5fed3de5b062a1a0837fd02286e0a9.

I benchmarked an improvement in CCR and found that changes introduced in 
#67190 made CCR 10 times slower (1816 seconds to 26515 seconds).

"total_read_remote_exec_time_millis" : 26515182
"total_read_remote_exec_time_millis" : 1816094

With concurrent indexing and Lucene merges, documents in segments are no 
longer sorted by sequence numbers. And if the index sorting is
specified, documents are never sorted by sequence numbers. Using a
mergeInstance stored field reader will decompress the whole block, which
we will not use.

Reverts #67190

server/src/main/java/org/elasticsearch/index/engine/LuceneChangesSnapshot.java

@@ -23,7 +23,6 @@ import org.apache.lucene.search.TopDocs;
 import org.apache.lucene.util.ArrayUtil;
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.lucene.Lucene;
-import org.elasticsearch.common.lucene.index.SequentialStoredFieldsLeafReader;
 import org.elasticsearch.common.lucene.search.Queries;
 import org.elasticsearch.core.internal.io.IOUtils;
 import org.elasticsearch.index.fieldvisitor.FieldsVisitor;
@@ -219,12 +218,8 @@ final class LuceneChangesSnapshot implements Translog.Snapshot {
         final String sourceField = parallelArray.hasRecoverySource[docIndex] ? SourceFieldMapper.RECOVERY_SOURCE_NAME :
             SourceFieldMapper.NAME;
         final FieldsVisitor fields = new FieldsVisitor(true, sourceField);
-        if (leaf.reader() instanceof SequentialStoredFieldsLeafReader) {
-            ((SequentialStoredFieldsLeafReader) leaf.reader()).getSequentialStoredFieldsReader().visitDocument(segmentDocID, fields);
-        } else {
-            assert false : "The changes reader isn't wrapped with Lucene#wrapAllDocsLive";
-            throw new IllegalStateException("The changes reader isn't wrapped with Lucene#wrapAllDocsLive");
-        }
+        leaf.reader().document(segmentDocID, fields);
+
         final Translog.Operation op;
         final boolean isTombstone = parallelArray.isTombStone[docIndex];
         if (isTombstone && fields.id() == null) {

test/framework/src/main/java/org/elasticsearch/test/engine/ThrowingLeafReaderWrapper.java

@@ -8,9 +8,9 @@
 
 package org.elasticsearch.test.engine;
 
-import org.apache.lucene.codecs.StoredFieldsReader;
 import org.apache.lucene.index.BinaryDocValues;
 import org.apache.lucene.index.Fields;
+import org.apache.lucene.index.FilterLeafReader;
 import org.apache.lucene.index.LeafReader;
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.index.PostingsEnum;
@@ -20,7 +20,6 @@ import org.apache.lucene.index.Terms;
 import org.apache.lucene.index.TermsEnum;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.automaton.CompiledAutomaton;
-import org.elasticsearch.common.lucene.index.SequentialStoredFieldsLeafReader;
 
 import java.io.IOException;
 
@@ -29,7 +28,7 @@ import java.io.IOException;
  * are called on is. This allows to test parts of the system under certain
  * error conditions that would otherwise not be possible.
  */
-public class ThrowingLeafReaderWrapper extends SequentialStoredFieldsLeafReader {
+public class ThrowingLeafReaderWrapper extends FilterLeafReader {
 
     private final Thrower thrower;
 
@@ -198,9 +197,4 @@ public class ThrowingLeafReaderWrapper extends SequentialStoredFieldsLeafReader
     public CacheHelper getReaderCacheHelper() {
         return in.getReaderCacheHelper();
     }
-
-    @Override
-    protected StoredFieldsReader doGetSequentialStoredFieldsReader(StoredFieldsReader reader) {
-        return reader;
-    }
 }