VOL-2265 test go.mod and vendor consistency;
Update dependencies to resolve `410 Gone` errors when fetching modules

Change-Id: If0bdbc1b6d629ce819b9fa4701c016df812f92d5
diff --git a/vendor/golang.org/x/net/http2/frame.go b/vendor/golang.org/x/net/http2/frame.go
index 514c126..b46791d 100644
--- a/vendor/golang.org/x/net/http2/frame.go
+++ b/vendor/golang.org/x/net/http2/frame.go
@@ -643,7 +643,7 @@
 	return f.WriteDataPadded(streamID, endStream, data, nil)
 }
 
-// WriteDataPadded writes a DATA frame with optional padding.
+// WriteData writes a DATA frame with optional padding.
 //
 // If pad is nil, the padding bit is not sent.
 // The length of pad must not exceed 255 bytes.
diff --git a/vendor/golang.org/x/net/http2/server.go b/vendor/golang.org/x/net/http2/server.go
index d4abeb2..6f8e8b0 100644
--- a/vendor/golang.org/x/net/http2/server.go
+++ b/vendor/golang.org/x/net/http2/server.go
@@ -52,10 +52,11 @@
 )
 
 const (
-	prefaceTimeout        = 10 * time.Second
-	firstSettingsTimeout  = 2 * time.Second // should be in-flight with preface anyway
-	handlerChunkWriteSize = 4 << 10
-	defaultMaxStreams     = 250 // TODO: make this 100 as the GFE seems to?
+	prefaceTimeout         = 10 * time.Second
+	firstSettingsTimeout   = 2 * time.Second // should be in-flight with preface anyway
+	handlerChunkWriteSize  = 4 << 10
+	defaultMaxStreams      = 250 // TODO: make this 100 as the GFE seems to?
+	maxQueuedControlFrames = 10000
 )
 
 var (
@@ -163,6 +164,15 @@
 	return defaultMaxStreams
 }
 
+// maxQueuedControlFrames is the maximum number of control frames like
+// SETTINGS, PING and RST_STREAM that will be queued for writing before
+// the connection is closed to prevent memory exhaustion attacks.
+func (s *Server) maxQueuedControlFrames() int {
+	// TODO: if anybody asks, add a Server field, and remember to define the
+	// behavior of negative values.
+	return maxQueuedControlFrames
+}
+
 type serverInternalState struct {
 	mu          sync.Mutex
 	activeConns map[*serverConn]struct{}
@@ -482,6 +492,7 @@
 	sawFirstSettings            bool // got the initial SETTINGS frame after the preface
 	needToSendSettingsAck       bool
 	unackedSettings             int    // how many SETTINGS have we sent without ACKs?
+	queuedControlFrames         int    // control frames in the writeSched queue
 	clientMaxStreams            uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit)
 	advMaxStreams               uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client
 	curClientStreams            uint32 // number of open streams initiated by the client
@@ -870,6 +881,14 @@
 			}
 		}
 
+		// If the peer is causing us to generate a lot of control frames,
+		// but not reading them from us, assume they are trying to make us
+		// run out of memory.
+		if sc.queuedControlFrames > sc.srv.maxQueuedControlFrames() {
+			sc.vlogf("http2: too many control frames in send queue, closing connection")
+			return
+		}
+
 		// Start the shutdown timer after sending a GOAWAY. When sending GOAWAY
 		// with no error code (graceful shutdown), don't start the timer until
 		// all open streams have been completed.
@@ -1069,6 +1088,14 @@
 	}
 
 	if !ignoreWrite {
+		if wr.isControl() {
+			sc.queuedControlFrames++
+			// For extra safety, detect wraparounds, which should not happen,
+			// and pull the plug.
+			if sc.queuedControlFrames < 0 {
+				sc.conn.Close()
+			}
+		}
 		sc.writeSched.Push(wr)
 	}
 	sc.scheduleFrameWrite()
@@ -1186,10 +1213,8 @@
 // If a frame is already being written, nothing happens. This will be called again
 // when the frame is done being written.
 //
-// If a frame isn't being written we need to send one, the best frame
-// to send is selected, preferring first things that aren't
-// stream-specific (e.g. ACKing settings), and then finding the
-// highest priority stream.
+// If a frame isn't being written and we need to send one, the best frame
+// to send is selected by writeSched.
 //
 // If a frame isn't being written and there's nothing else to send, we
 // flush the write buffer.
@@ -1217,6 +1242,9 @@
 		}
 		if !sc.inGoAway || sc.goAwayCode == ErrCodeNo {
 			if wr, ok := sc.writeSched.Pop(); ok {
+				if wr.isControl() {
+					sc.queuedControlFrames--
+				}
 				sc.startFrameWrite(wr)
 				continue
 			}
@@ -1509,6 +1537,8 @@
 	if err := f.ForeachSetting(sc.processSetting); err != nil {
 		return err
 	}
+	// TODO: judging by RFC 7540, Section 6.5.3 each SETTINGS frame should be
+	// acknowledged individually, even if multiple are received before the ACK.
 	sc.needToSendSettingsAck = true
 	sc.scheduleFrameWrite()
 	return nil
@@ -2307,16 +2337,7 @@
 
 func (cw chunkWriter) Write(p []byte) (n int, err error) { return cw.rws.writeChunk(p) }
 
-func (rws *responseWriterState) hasTrailers() bool { return len(rws.trailers) > 0 }
-
-func (rws *responseWriterState) hasNonemptyTrailers() bool {
-	for _, trailer := range rws.trailers {
-		if _, ok := rws.handlerHeader[trailer]; ok {
-			return true
-		}
-	}
-	return false
-}
+func (rws *responseWriterState) hasTrailers() bool { return len(rws.trailers) != 0 }
 
 // declareTrailer is called for each Trailer header when the
 // response header is written. It notes that a header will need to be
@@ -2416,10 +2437,7 @@
 		rws.promoteUndeclaredTrailers()
 	}
 
-	// only send trailers if they have actually been defined by the
-	// server handler.
-	hasNonemptyTrailers := rws.hasNonemptyTrailers()
-	endStream := rws.handlerDone && !hasNonemptyTrailers
+	endStream := rws.handlerDone && !rws.hasTrailers()
 	if len(p) > 0 || endStream {
 		// only send a 0 byte DATA frame if we're ending the stream.
 		if err := rws.conn.writeDataFromHandler(rws.stream, p, endStream); err != nil {
@@ -2428,7 +2446,7 @@
 		}
 	}
 
-	if rws.handlerDone && hasNonemptyTrailers {
+	if rws.handlerDone && rws.hasTrailers() {
 		err = rws.conn.writeHeaders(rws.stream, &writeResHeaders{
 			streamID:  rws.stream.id,
 			h:         rws.handlerHeader,
diff --git a/vendor/golang.org/x/net/http2/transport.go b/vendor/golang.org/x/net/http2/transport.go
index c0c80d8..f272e8f 100644
--- a/vendor/golang.org/x/net/http2/transport.go
+++ b/vendor/golang.org/x/net/http2/transport.go
@@ -28,7 +28,6 @@
 	"strconv"
 	"strings"
 	"sync"
-	"sync/atomic"
 	"time"
 
 	"golang.org/x/net/http/httpguts"
@@ -200,7 +199,6 @@
 	t         *Transport
 	tconn     net.Conn             // usually *tls.Conn, except specialized impls
 	tlsState  *tls.ConnectionState // nil only for specialized impls
-	reused    uint32               // whether conn is being reused; atomic
 	singleUse bool                 // whether being used for a single http.Request
 
 	// readLoop goroutine fields:
@@ -442,8 +440,7 @@
 			t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err)
 			return nil, err
 		}
-		reused := !atomic.CompareAndSwapUint32(&cc.reused, 0, 1)
-		traceGotConn(req, cc, reused)
+		traceGotConn(req, cc)
 		res, gotErrAfterReqBodyWrite, err := cc.roundTrip(req)
 		if err != nil && retry <= 6 {
 			if req, err = shouldRetryRequest(req, err, gotErrAfterReqBodyWrite); err == nil {
@@ -1414,11 +1411,7 @@
 		// followed by the query production (see Sections 3.3 and 3.4 of
 		// [RFC3986]).
 		f(":authority", host)
-		m := req.Method
-		if m == "" {
-			m = http.MethodGet
-		}
-		f(":method", m)
+		f(":method", req.Method)
 		if req.Method != "CONNECT" {
 			f(":path", path)
 			f(":scheme", req.URL.Scheme)
@@ -2562,15 +2555,15 @@
 	trace.GetConn(hostPort)
 }
 
-func traceGotConn(req *http.Request, cc *ClientConn, reused bool) {
+func traceGotConn(req *http.Request, cc *ClientConn) {
 	trace := httptrace.ContextClientTrace(req.Context())
 	if trace == nil || trace.GotConn == nil {
 		return
 	}
 	ci := httptrace.GotConnInfo{Conn: cc.tconn}
-	ci.Reused = reused
 	cc.mu.Lock()
-	ci.WasIdle = len(cc.streams) == 0 && reused
+	ci.Reused = cc.nextStreamID > 1
+	ci.WasIdle = len(cc.streams) == 0 && ci.Reused
 	if ci.WasIdle && !cc.lastActive.IsZero() {
 		ci.IdleTime = time.Now().Sub(cc.lastActive)
 	}
diff --git a/vendor/golang.org/x/net/http2/writesched.go b/vendor/golang.org/x/net/http2/writesched.go
index 4fe3073..f24d2b1 100644
--- a/vendor/golang.org/x/net/http2/writesched.go
+++ b/vendor/golang.org/x/net/http2/writesched.go
@@ -32,7 +32,7 @@
 
 	// Pop dequeues the next frame to write. Returns false if no frames can
 	// be written. Frames with a given wr.StreamID() are Pop'd in the same
-	// order they are Push'd.
+	// order they are Push'd. No frames should be discarded except by CloseStream.
 	Pop() (wr FrameWriteRequest, ok bool)
 }
 
@@ -76,6 +76,12 @@
 	return wr.stream.id
 }
 
+// isControl reports whether wr is a control frame for MaxQueuedControlFrames
+// purposes. That includes non-stream frames and RST_STREAM frames.
+func (wr FrameWriteRequest) isControl() bool {
+	return wr.stream == nil
+}
+
 // DataSize returns the number of flow control bytes that must be consumed
 // to write this entire frame. This is 0 for non-DATA frames.
 func (wr FrameWriteRequest) DataSize() int {