vendor: update buildkit to b4a6a0e3

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

go.mod

@@ -55,7 +55,7 @@ require (
 	github.com/mattn/go-sqlite3 v1.10.0 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
 	github.com/miekg/pkcs11 v0.0.0-20190322140431-074fd7a1ed19 // indirect
-	github.com/moby/buildkit v0.4.1-0.20190405144722-cbfb5c476a09
+	github.com/moby/buildkit v0.4.1-0.20190410165125-b4a6a0e3a7d1
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/opencontainers/go-digest v1.0.0-rc1

go.sum

@@ -185,8 +185,8 @@ github.com/miekg/pkcs11 v0.0.0-20190322140431-074fd7a1ed19/go.mod h1:WCBAbTOdfhH
 github.com/mitchellh/hashstructure v0.0.0-20170609045927-2bca23e0e452/go.mod h1:QjSHrPWS+BGUVBYkbTZWEnOh3G1DutKwClXU/ABz6AQ=
 github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
-github.com/moby/buildkit v0.4.1-0.20190405144722-cbfb5c476a09 h1:OHOk/ObJ9P40As+zA6PNN8w1ZulvpVQyYtSzkWjDEyQ=
+github.com/moby/buildkit v0.4.1-0.20190410165125-b4a6a0e3a7d1 h1:e8eXboh2H1zYsGDo/nPuZQReAd2eGEtQV1AFX9BncWo=
-github.com/moby/buildkit v0.4.1-0.20190405144722-cbfb5c476a09/go.mod h1:ivyIn0/bTW+YAXWeOqMWJ9aHLeac6SKIB4QeGlxzu/Q=
+github.com/moby/buildkit v0.4.1-0.20190410165125-b4a6a0e3a7d1/go.mod h1:ivyIn0/bTW+YAXWeOqMWJ9aHLeac6SKIB4QeGlxzu/Q=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v1.0.1 h1:9f412s+6RmYXLWZSEzVVgPGK7C2PphHj5RJrvfx9AWI=

vendor/github.com/moby/buildkit/util/progress/progressui/display.go

@@ -227,7 +227,10 @@ func (t *trace) update(s *client.SolveStatus, termWidth int) {
 			}
 			t.vertexes = append(t.vertexes, t.byDigest[v.Digest])
 		}
+		// allow a duplicate initial vertex that shouldn't reset state
+		if !(prev != nil && prev.Started != nil && v.Started == nil) {
 			t.byDigest[v.Digest].Vertex = v
+		}
 		t.byDigest[v.Digest].jobCached = false
 	}
 	for _, s := range s.Statuses {

vendor/modules.txt

@@ -269,7 +269,7 @@ github.com/matttproud/golang_protobuf_extensions/pbutil
 github.com/miekg/pkcs11
 # github.com/mitchellh/mapstructure v1.1.2
 github.com/mitchellh/mapstructure
-# github.com/moby/buildkit v0.4.1-0.20190405144722-cbfb5c476a09
+# github.com/moby/buildkit v0.4.1-0.20190410165125-b4a6a0e3a7d1
 github.com/moby/buildkit/session/auth/authprovider
 github.com/moby/buildkit/client
 github.com/moby/buildkit/session