Remove unused xid parameter.

Commit 6c2003f removes the use of transaction id's for exporting
snapshots. This commit removes one unused xid parameter left behind in
SnapBuildGetOrBuildSnapshot.

Author: Melih Mutlu
Reviewed-By: Zhang Mingli
Discussion: https://postgr.es/m/CAGPVpCTqZRoDKgCycw+eYi+Gq41rN9pU-gntgTd7wfsNDpPL3Q@mail.gmail.com

Author: Amit Kapila

src/backend/replication/logical/decode.c

@@ -594,7 +594,7 @@ logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf)
 			  SnapBuildXactNeedsSkip(builder, buf->origptr)))
 		return;
 
-	snapshot = SnapBuildGetOrBuildSnapshot(builder, xid);
+	snapshot = SnapBuildGetOrBuildSnapshot(builder);
 	ReorderBufferQueueMessage(ctx->reorder, xid, snapshot, buf->endptr,
 							  message->transactional,
 							  message->message, /* first part of message is

src/backend/replication/logical/snapbuild.c

@@ -694,7 +694,7 @@ SnapBuildExportSnapshot(SnapBuild *builder)
  * Ensure there is a snapshot and if not build one for current transaction.
  */
 Snapshot
-SnapBuildGetOrBuildSnapshot(SnapBuild *builder, TransactionId xid)
+SnapBuildGetOrBuildSnapshot(SnapBuild *builder)
 {
 	Assert(builder->state == SNAPBUILD_CONSISTENT);
 

src/include/replication/snapbuild.h

@@ -73,8 +73,7 @@ extern void SnapBuildClearExportedSnapshot(void);
 extern void SnapBuildResetExportedSnapshotState(void);
 
 extern SnapBuildState SnapBuildCurrentState(SnapBuild *builder);
-extern Snapshot SnapBuildGetOrBuildSnapshot(SnapBuild *builder,
-											TransactionId xid);
+extern Snapshot SnapBuildGetOrBuildSnapshot(SnapBuild *builder);
 
 extern bool SnapBuildXactNeedsSkip(SnapBuild *builder, XLogRecPtr ptr);
 extern XLogRecPtr SnapBuildGetTwoPhaseAt(SnapBuild *builder);