Endpoints: This CL changes endpoint to be a plain struct defined in v23.

MultiPart: 3/5
Change-Id: I05b8d2f52daf9d6f2e6b36a85de292899923c958
diff --git a/v23/security/call.go b/v23/security/call.go
index 4bbb922..f577432 100644
--- a/v23/security/call.go
+++ b/v23/security/call.go
@@ -14,7 +14,6 @@
 	jutil "v.io/x/jni/util"
 	jcontext "v.io/x/jni/v23/context"
 
-	"v.io/v23"
 	"v.io/v23/context"
 	"v.io/v23/naming"
 	"v.io/v23/security"
@@ -119,10 +118,10 @@
 
 func (c *callImpl) LocalEndpoint() naming.Endpoint {
 	epStr := c.callStringMethod("localEndpoint")
-	ep, err := v23.NewEndpoint(epStr)
+	ep, err := naming.ParseEndpoint(epStr)
 	if err != nil {
 		log.Printf("Couldn't parse endpoint string %q: %v", epStr, err)
-		return nil
+		return naming.Endpoint{}
 	}
 	return ep
 }
@@ -177,10 +176,10 @@
 
 func (c *callImpl) RemoteEndpoint() naming.Endpoint {
 	epStr := c.callStringMethod("remoteEndpoint")
-	ep, err := v23.NewEndpoint(epStr)
+	ep, err := naming.ParseEndpoint(epStr)
 	if err != nil {
 		log.Printf("Couldn't parse endpoint string %q: %v", epStr, err)
-		return nil
+		return naming.Endpoint{}
 	}
 	return ep
 }