Use the correct error

When the state provider isn't able to do its job because the chain is lagging
behind head, it's supposed to use a predefined error from the l2stateprovider
package. Instead, the nitro implemention of the provider was using a
redefinition of the error.

While this coding error easily accounts for why there were a bunch of ERROR logs
about the chain's not keeping up with the latest changes, it does not explain
why the test is sometimes flaky. I suspect that the original commits in this PR
were chasing the ERROR logs in the flaky tests, but that those were not the root
cause of the test failures.

staker/bold/bold_state_provider.go

@@ -38,10 +38,6 @@ var (
 
 var executionNodeOfflineGauge = metrics.NewRegisteredGauge("arb/state_provider/execution_node_offline", nil)
 
-var (
-	ErrChainCatchingUp = errors.New("chain catching up")
-)
-
 type BOLDStateProvider struct {
 	validator                *staker.BlockValidator
 	statelessValidator       *staker.StatelessBlockValidator
@@ -171,7 +167,7 @@ func (s *BOLDStateProvider) isStateValidatedAndMessageCountPastThreshold(
 		return false, err
 	}
 	if lastValidatedGs == nil {
-		return false, ErrChainCatchingUp
+		return false, l2stateprovider.ErrChainCatchingUp
 	}
 	stateValidated := gs.Batch < lastValidatedGs.GlobalState.Batch || (gs.Batch == lastValidatedGs.GlobalState.Batch && gs.PosInBatch <= lastValidatedGs.GlobalState.PosInBatch)
 	return stateValidated, nil

system_tests/bold_new_challenge_test.go

@@ -157,23 +157,6 @@ func testChallengeProtocolBOLDVirtualBlocks(t *testing.T, wrongAtFirstVirtual bo
 	builder.L1Info.GenerateAccount("EvilAsserter")
 	fundBoldStaker(t, ctx, builder, "EvilAsserter")
 
-	TransferBalance(t, "Faucet", "Faucet", common.Big0, builder.L2Info, builder.L2.Client, ctx)
-
-	// Wait for both nodes' chains to catch up to at least a batch that includes the self-transfer
-	// from above. This makes sure that nodes have at least caught up to the required rollup chain state
-	// by reading batches from the parent chain.
-	nodeAExec := builder.L2.ExecNode
-	nodeBExec := evilNode.ExecNode
-	for {
-		nodeALatest := nodeAExec.Backend.APIBackend().CurrentHeader()
-		nodeBLatest := nodeBExec.Backend.APIBackend().CurrentHeader()
-		isCaughtUp := nodeALatest.Number.Uint64() == 2
-		areEqual := nodeALatest.Number.Uint64() == nodeBLatest.Number.Uint64()
-		if isCaughtUp && areEqual {
-			break
-		}
-	}
-
 	assertionChain, cleanupHonestChallengeManager := startBoldChallengeManager(t, ctx, builder, builder.L2, "HonestAsserter", nil)
 	defer cleanupHonestChallengeManager()
 
@@ -190,6 +173,8 @@ func testChallengeProtocolBOLDVirtualBlocks(t *testing.T, wrongAtFirstVirtual bo
 	})
 	defer cleanupEvilChallengeManager()
 
+	TransferBalance(t, "Faucet", "Faucet", common.Big0, builder.L2Info, builder.L2.Client, ctx)
+
 	// Everything's setup, now just wait for the challenge to complete and ensure the honest party won
 
 	chalManager := assertionChain.SpecChallengeManager()