VOL-2868 Remove all uses of Proxy.RegisterCallback(...)

Change-Id: I05d47a9915071adb80ebc3c5f9b129ed6c36b54b
diff --git a/rw_core/core/device_state_transitions.go b/rw_core/core/device_state_transitions.go
index b8acafc..5c55b7c 100644
--- a/rw_core/core/device_state_transitions.go
+++ b/rw_core/core/device_state_transitions.go
@@ -68,7 +68,7 @@
 }
 
 // TransitionHandler function type which takes the current and previous device info as input parameter
-type TransitionHandler func(ctx context.Context, curr *voltha.Device, prev *voltha.Device) error
+type TransitionHandler func(context.Context, *voltha.Device) error
 
 // Transition represent transition related attributes
 type Transition struct {
@@ -284,11 +284,10 @@
 	return transition.handlers, m
 }
 
-// GetTransitionHandler returns transition handler
-func (tMap *TransitionMap) GetTransitionHandler(pDevice *voltha.Device, cDevice *voltha.Device) []TransitionHandler {
+// GetTransitionHandler returns transition handler & a flag that's set if the transition is invalid
+func (tMap *TransitionMap) GetTransitionHandler(device *voltha.Device, pState *DeviceState) []TransitionHandler {
 	//1. Get the previous and current set of states
-	pState := getDeviceStates(pDevice)
-	cState := getDeviceStates(cDevice)
+	cState := getDeviceStates(device)
 
 	// Do nothing is there are no states change
 	if *pState == *cState {
@@ -297,11 +296,11 @@
 
 	//logger.Infow("DeviceType", log.Fields{"device": pDevice})
 	deviceType := parent
-	if !pDevice.Root {
+	if !device.Root {
 		logger.Info("device is child")
 		deviceType = child
 	}
-	logger.Infof("deviceType:%d-deviceId:%s-previous:%v-current:%v", deviceType, pDevice.Id, pState, cState)
+	logger.Infof("deviceType:%d-deviceId:%s-previous:%v-current:%v", deviceType, device.Id, pState, cState)
 
 	//2. Go over transition array to get the right transition
 	var currentMatch []TransitionHandler