Revert "Fix error message when chain head changes (#3972)" (#4022)

This reverts commit 9c77692.

ironfish/src/blockchain/blockchain.ts

@@ -968,7 +968,7 @@ export class Blockchain {
         }
 
         if (previous && !previous.hash.equals(previousBlockHash)) {
-          throw new HeadChangedError(`Can't create a block not attached to the chain head`)
+          throw new Error('Cannot create a block with a previous header that does not match')
         }
 
         target = Target.calculateTarget(
@@ -1520,7 +1520,3 @@ export class VerifyError extends Error {
     this.score = score
   }
 }
-
-export class HeadChangedError extends Error {
-  name = this.constructor.name
-}

ironfish/src/mining/manager.ts

@@ -4,7 +4,7 @@
 
 import { BufferSet } from 'buffer-map'
 import { Assert } from '../assert'
-import { Blockchain, HeadChangedError } from '../blockchain'
+import { Blockchain } from '../blockchain'
 import { isExpiredSequence } from '../consensus'
 import { Event } from '../event'
 import { MemPool } from '../memPool'
@@ -66,17 +66,9 @@ export class MiningManager {
     this.chain.onConnectBlock.on(
       (block) =>
         void this.onConnectedBlock(block).catch((error) => {
-          if (error instanceof HeadChangedError) {
-            this.node.logger.debug(
-              `Chain head changed while creating block template for sequence ${
-                block.header.sequence + 1
-              }`,
-            )
-          } else {
-            this.node.logger.error(
-              `Error creating block template: ${ErrorUtils.renderError(error)}`,
-            )
-          }
+          this.node.logger.info(
+            `Error creating block template: ${ErrorUtils.renderError(error)}`,
+          )
         }),
     )
   }