godep: update etcd to 3.0.12

vendor/github.com/xiang90/probing/prober.go

@@ -61,7 +61,7 @@ func (p *prober) AddHTTP(id string, probingInterval time.Duration, endpoints []s
 				}
 				resp, err := p.tr.RoundTrip(req)
 				if err != nil {
-					s.recordFailure()
+					s.recordFailure(err)
 					pinned = (pinned + 1) % len(endpoints)
 					continue
 				}
@@ -71,7 +71,7 @@ func (p *prober) AddHTTP(id string, probingInterval time.Duration, endpoints []s
 				err = d.Decode(&hh)
 				resp.Body.Close()
 				if err != nil || !hh.OK {
-					s.recordFailure()
+					s.recordFailure(err)
 					pinned = (pinned + 1) % len(endpoints)
 					continue
 				}

vendor/github.com/xiang90/probing/status.go

@@ -14,6 +14,7 @@ type Status interface {
 	Total() int64
 	Loss() int64
 	Health() bool
+	Err() error
 	// Estimated smoothed round trip time
 	SRTT() time.Duration
 	// Estimated clock difference
@@ -27,6 +28,7 @@ type status struct {
 	total     int64
 	loss      int64
 	health    bool
+	err       error
 	clockdiff time.Duration
 	stopC     chan struct{}
 }
@@ -56,6 +58,12 @@ func (s *status) Health() bool {
 	return s.health
 }
 
+func (s *status) Err() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.err
+}
+
 func (s *status) ClockDiff() time.Duration {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -74,15 +82,17 @@ func (s *status) record(rtt time.Duration, when time.Time) {
 	s.health = true
 	s.srtt = time.Duration((1-α)*float64(s.srtt) + α*float64(rtt))
 	s.clockdiff = time.Now().Sub(when) - s.srtt/2
+	s.err = nil
 }
 
-func (s *status) recordFailure() {
+func (s *status) recordFailure(err error) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
 	s.total++
 	s.health = false
 	s.loss += 1
+	s.err = err
 }
 
 func (s *status) reset() {
@@ -91,6 +101,8 @@ func (s *status) reset() {
 
 	s.srtt = 0
 	s.total = 0
+	s.loss = 0
 	s.health = false
 	s.clockdiff = 0
+	s.err = nil
 }