Use a constructor properly in change tracker unit tests

newFakeProxier was inlining the details of NewEndpointsChangeTracker
so it could override trackerStartTime, but it would be better and more
future-proof to just call NewEndpointsChangeTracker normally and then
edit that one field.

(Also remove an unused FakeProxier field.)

pkg/proxy/endpointschangetracker_test.go

@@ -1037,7 +1037,6 @@ func TestUpdateEndpointsMap(t *testing.T) {
 	for tci, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			fp := newFakeProxier(v1.IPv4Protocol, time.Time{})
-			fp.hostname = testHostname
 
 			// First check that after adding all previous versions of endpoints,
 			// the fp.previousEndpointsMap is as we expect.

pkg/proxy/endpointslicecache_test.go

@@ -610,7 +610,6 @@ func TestEndpointSliceCacheClearedCorrectly(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			fp := newFakeProxier(v1.IPv4Protocol, time.Time{})
-			fp.hostname = testHostname
 
 			for _, epSlice := range tc.currEndpointSlices {
 				fp.addEndpointSlice(epSlice)
@@ -648,7 +647,6 @@ func TestSameServiceEndpointSliceCacheClearedCorrectly(t *testing.T) {
 	}
 
 	fp := newFakeProxier(v1.IPv4Protocol, time.Time{})
-	fp.hostname = testHostname
 
 	for _, epSlice := range currEndpointSlices {
 		fp.addEndpointSlice(epSlice)

pkg/proxy/servicechangetracker_test.go

@@ -621,20 +621,16 @@ type FakeProxier struct {
 	serviceChanges   *ServiceChangeTracker
 	svcPortMap       ServicePortMap
 	endpointsMap     EndpointsMap
-	hostname         string
 }
 
 func newFakeProxier(ipFamily v1.IPFamily, t time.Time) *FakeProxier {
+	ect := NewEndpointsChangeTracker(testHostname, nil, ipFamily, nil, nil)
+	ect.trackerStartTime = t
 	return &FakeProxier{
-		svcPortMap:     make(ServicePortMap),
-		serviceChanges: NewServiceChangeTracker(nil, ipFamily, nil, nil),
-		endpointsMap:   make(EndpointsMap),
-		endpointsChanges: &EndpointsChangeTracker{
-			lastChangeTriggerTimes:    make(map[types.NamespacedName][]time.Time),
-			trackerStartTime:          t,
-			processEndpointsMapChange: nil,
-			endpointSliceCache:        NewEndpointSliceCache(testHostname, ipFamily, nil, nil),
-		},
+		svcPortMap:       make(ServicePortMap),
+		serviceChanges:   NewServiceChangeTracker(nil, ipFamily, nil, nil),
+		endpointsMap:     make(EndpointsMap),
+		endpointsChanges: ect,
 	}
 }