wdb-migration: skip already migrated parts in TXCountTimeIndex.

lib/wallet/migrations.js

@@ -869,6 +869,7 @@ class MigrateTXCountTimeIndex extends AbstractMigration {
       const [height] = this.layout.wdb.h.decode(key);
       const hash = value.slice(0, 32);
 
+      // Skip if already migrated.
       if (value.length === 40)
         continue;
 
@@ -958,6 +959,8 @@ class MigrateTXCountTimeIndex extends AbstractMigration {
       lte: txlayout.m.max()
     });
 
+    // Here we don't need to skip as the old time index
+    // is getting cleaned up in the same migration.
     for await (const {key} of txsByOldTime) {
       const [, txHash] = txlayout.m.decode(key);
       await this.migrateTX(bucket, wid, txHash);
@@ -978,6 +981,11 @@ class MigrateTXCountTimeIndex extends AbstractMigration {
 
   async migrateTX(bucket, wid, txHash, block, extra) {
     const txlayout = this.layout.txdb;
+
+    // Skip if already migrated.
+    if (await bucket.get(txlayout.y.encode(txHash)))
+      return;
+
     const batch = bucket.batch();
     /** @type {Set<Number>} */
     const accounts = new Set();