Grammar and typos corrections according to Jianjun's comments.

Including files:
- docs/feature-gates.md
- pkg/agent/proxy/endpoints.go
- pkg/agent/proxy/endpointslicecache.go

docs/feature-gates.md

@@ -60,10 +60,11 @@ NetworkPolicy implementation for Pod-to-Service traffic.
 
 `EndpointSlice` enables Service EndpointSlice support in AntreaProxy. The
 EndpointSlice API was introduced in Kubernetes 1.16 (alpha) and it is enabled
-by default in Kubernetes 1.17 (beta). This flag will take no effect if AntreaProxy
-is not enabled. The endpoint conditions of `Serving` and `Terminating` are not
-supported currently. ServiceTopology is not supported either. Refer to this [link](https://kubernetes.io/docs/tasks/administer-cluster/enabling-endpointslices/)
-for more information. EndpointSlice API version that AntreaProxy supports is v1beta1
+by default in Kubernetes 1.17 (beta). The EndpointSlice feature gate will take no
+effect if AntreaProxy is not enabled. The endpoint conditions of `Serving` and
+`Terminating` are not supported currently. ServiceTopology is not supported either.
+Refer to this [link](https://kubernetes.io/docs/tasks/administer-cluster/enabling-endpointslices/)
+for more information. The EndpointSlice API version that AntreaProxy supports is v1beta1
 currently, and other EndpointSlice API versions are not supported. If EndpointSlice is
 enabled in AntreaProxy, but EndpointSlice API is disabled in Kubernetes or EndpointSlice
 API version v1beta1 is not supported in Kubernetes, error messages will be logged by

pkg/agent/proxy/endpoints.go

@@ -114,17 +114,17 @@ func (t *endpointsChangesTracker) OnEndpointUpdate(previous, current *corev1.End
 func (t *endpointsChangesTracker) OnEndpointSliceUpdate(endpointSlice *discovery.EndpointSlice, removeSlice bool) bool {
 	// This should never happen.
 	if endpointSlice == nil {
-		klog.Error("Nil endpointSlice passed to EndpointSliceUpdate")
+		klog.Error("Nil EndpointSlice passed to EndpointSliceUpdate")
 		return false
 	}
 
 	if _, has := supportedEndpointSliceAddressTypes[endpointSlice.AddressType]; !has {
-		klog.V(4).Infof("EndpointSlice address type not supported: %s", endpointSlice.AddressType)
+		klog.V(4).Infof("EndpointSlice address type is not supported: %s", endpointSlice.AddressType)
 		return false
 	}
 
 	if _, _, err := endpointSliceCacheKeys(endpointSlice); err != nil {
-		klog.Warningf("Error getting endpoint slice cache keys: %v", err)
+		klog.Warningf("Got EndpointSlice cache keys with error: %v", err)
 		return false
 	}
 

pkg/agent/proxy/endpointslicecache.go

@@ -28,7 +28,7 @@ limitations under the License.
 // limitations under the License.
 //
 // Original file https://raw.githubusercontent.com/kubernetes/kubernetes/0c0d4fea8dd6bdcd16b9e1d35da3f7d209341a6f/pkg/proxy/endpointslicecache.go
-// If this file is located in third_party, there will be an import cycle issue when build Antrea as this file import
+// If this file is located in third_party, there will be an import cycle issue when building Antrea as this file imports
 // "github.com/vmware-tanzu/antrea/pkg/agent/proxy/types".
 // Remove makeEndpointInfo and recorder in fields.
 // Remove unused standardEndpointInfo.