fix: revert spec breaking changes

protocol/v2/qbft/controller/controller.go

@@ -53,26 +53,26 @@ func NewController(
 }
 
 // StartNewInstance will start a new QBFT instance, if can't will return error
-func (c *Controller) StartNewInstance(logger *zap.Logger, height specqbft.Height, value []byte) (*instance.Instance, error) {
+func (c *Controller) StartNewInstance(logger *zap.Logger, height specqbft.Height, value []byte) error {
+
 	if err := c.GetConfig().GetValueCheckF()(value); err != nil {
-		return nil, errors.Wrap(err, "value invalid")
+		return errors.Wrap(err, "value invalid")
 	}
 
 	if height < c.Height {
-		return nil, errors.New("attempting to start an instance with a past height")
+		return errors.New("attempting to start an instance with a past height")
 	}
 
 	if c.StoredInstances.FindInstance(height) != nil {
-		return nil, errors.New("instance already running")
+		return errors.New("instance already running")
 	}
 
 	c.Height = height
 
 	newInstance := c.addAndStoreNewInstance()
 	newInstance.Start(logger, value, height)
 	c.forceStopAllInstanceExceptCurrent()
-
-	return newInstance, nil
+	return nil
 }
 
 func (c *Controller) forceStopAllInstanceExceptCurrent() {

protocol/v2/qbft/spectest/controller_type.go

@@ -148,7 +148,7 @@ func testBroadcastedDecided(
 }
 
 func runInstanceWithData(t *testing.T, logger *zap.Logger, height specqbft.Height, contr *controller.Controller, runData *spectests.RunInstanceData) error {
-	_, err := contr.StartNewInstance(logger, height, runData.InputValue)
+	err := contr.StartNewInstance(logger, height, runData.InputValue)
 	var lastErr error
 	if err != nil {
 		lastErr = err

protocol/v2/ssv/runner/runner.go

@@ -300,13 +300,16 @@ func (b *BaseRunner) decide(logger *zap.Logger, runner Runner, slot phase0.Slot,
 		return errors.Wrap(err, "input data invalid")
 	}
 
-	newInstance, err := runner.GetBaseRunner().QBFTController.StartNewInstance(logger,
+	if err := runner.GetBaseRunner().QBFTController.StartNewInstance(logger,
 		specqbft.Height(slot),
 		byts,
-	)
-	if err != nil {
+	); err != nil {
 		return errors.Wrap(err, "could not start new QBFT instance")
 	}
+	newInstance := runner.GetBaseRunner().QBFTController.StoredInstances.FindInstance(specqbft.Height(slot)) // TODO confirm correctness
+	if newInstance == nil {
+		return errors.New("could not find newly created QBFT instance")
+	}
 
 	runner.GetBaseRunner().State.RunningInstance = newInstance