core: fix blockchain goroutine leaks in tests

core/genesis_test.go

@@ -120,6 +120,8 @@ func TestSetupGenesis(t *testing.T) {
 				// Advance to block #4, past the homestead transition block of customg.
 				genesis := oldcustomg.MustCommit(db)
 				bc, _ := NewBlockChain(db, oldcustomg.Config, ethash.NewFullFaker(), new(event.TypeMux), vm.Config{})
+				defer bc.Stop()
+
 				bc.SetValidator(bproc{})
 				bc.InsertChain(makeBlockChainWithDiff(genesis, []int{2, 3, 4, 5}, 0))
 				bc.CurrentBlock()