eth: enable bad block reports

We used to have reporting of bad blocks, but it was disabled
before the Frontier release. We need it back because users
are usually unable to provide the full RLP data of a bad
block when it occurs.

A shortcoming of this particular implementation is that the
origin peer is not tracked for blocks received during eth/63
sync. No origin peer info is still better than no report at
all though.

cmd/geth/main.go

@@ -244,6 +244,12 @@ JavaScript API. See https://github.com/ethereum/go-ethereum/wiki/Javascipt-Conso
 		// Start system runtime metrics collection
 		go metrics.CollectProcessMetrics(3 * time.Second)
 
+		// This should be the only place where reporting is enabled
+		// because it is not intended to run while testing.
+		// In addition to this check, bad block reports are sent only
+		// for chains with the main network genesis block and network id 1.
+		eth.EnableBadBlockReporting = true
+
 		utils.SetupNetwork(ctx)
 
 		// Deprecation warning.