diff --git a/vendor/google.golang.org/grpc/resolver/resolver.go b/vendor/google.golang.org/grpc/resolver/resolver.go
index e83da34..4c5423b 100644
--- a/vendor/google.golang.org/grpc/resolver/resolver.go
+++ b/vendor/google.golang.org/grpc/resolver/resolver.go
@@ -21,6 +21,10 @@
 package resolver
 
 import (
+	"context"
+	"net"
+
+	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/serviceconfig"
 )
 
@@ -86,9 +90,16 @@
 	// Type is the type of this address.
 	Type AddressType
 	// ServerName is the name of this address.
+	// If non-empty, the ServerName is used as the transport certification authority for
+	// the address, instead of the hostname from the Dial target string. In most cases,
+	// this should not be set.
 	//
-	// e.g. if Type is GRPCLB, ServerName should be the name of the remote load
+	// If Type is GRPCLB, ServerName should be the name of the remote load
 	// balancer, not the name of the backend.
+	//
+	// WARNING: ServerName must only be populated with trusted values. It
+	// is insecure to populate it with data from untrusted inputs since untrusted
+	// values could be used to bypass the authority checks performed by TLS.
 	ServerName string
 	// Metadata is the information associated with Addr, which may be used
 	// to make load balancing decision.
@@ -98,18 +109,38 @@
 // BuildOption includes additional information for the builder to create
 // the resolver.
 type BuildOption struct {
-	// DisableServiceConfig indicates whether resolver should fetch service config data.
+	// DisableServiceConfig indicates whether a resolver implementation should
+	// fetch service config data.
 	DisableServiceConfig bool
+	// DialCreds is the transport credentials used by the ClientConn for
+	// communicating with the target gRPC service (set via
+	// WithTransportCredentials). In cases where a name resolution service
+	// requires the same credentials, the resolver may use this field. In most
+	// cases though, it is not appropriate, and this field may be ignored.
+	DialCreds credentials.TransportCredentials
+	// CredsBundle is the credentials bundle used by the ClientConn for
+	// communicating with the target gRPC service (set via
+	// WithCredentialsBundle). In cases where a name resolution service
+	// requires the same credentials, the resolver may use this field. In most
+	// cases though, it is not appropriate, and this field may be ignored.
+	CredsBundle credentials.Bundle
+	// Dialer is the custom dialer used by the ClientConn for dialling the
+	// target gRPC service (set via WithDialer). In cases where a name
+	// resolution service requires the same dialer, the resolver may use this
+	// field. In most cases though, it is not appropriate, and this field may
+	// be ignored.
+	Dialer func(context.Context, string) (net.Conn, error)
 }
 
 // State contains the current Resolver state relevant to the ClientConn.
 type State struct {
-	Addresses []Address // Resolved addresses for the target
-	// ServiceConfig is the parsed service config; obtained from
-	// serviceconfig.Parse.
-	ServiceConfig serviceconfig.Config
+	// Addresses is the latest set of resolved addresses for the target.
+	Addresses []Address
 
-	// TODO: add Err error
+	// ServiceConfig contains the result from parsing the latest service
+	// config.  If it is nil, it indicates no service config is present or the
+	// resolver does not provide service configs.
+	ServiceConfig *serviceconfig.ParseResult
 }
 
 // ClientConn contains the callbacks for resolver to notify any updates
@@ -122,6 +153,10 @@
 type ClientConn interface {
 	// UpdateState updates the state of the ClientConn appropriately.
 	UpdateState(State)
+	// ReportError notifies the ClientConn that the Resolver encountered an
+	// error.  The ClientConn will notify the load balancer and begin calling
+	// ResolveNow on the Resolver with exponential backoff.
+	ReportError(error)
 	// NewAddress is called by resolver to notify ClientConn a new list
 	// of resolved addresses.
 	// The address list should be the complete list of resolved addresses.
@@ -133,6 +168,9 @@
 	//
 	// Deprecated: Use UpdateState instead.
 	NewServiceConfig(serviceConfig string)
+	// ParseServiceConfig parses the provided service config and returns an
+	// object that provides the parsed config.
+	ParseServiceConfig(serviceConfigJSON string) *serviceconfig.ParseResult
 }
 
 // Target represents a target for gRPC, as specified in: