Update vendor

vendor/github.com/google/go-containerregistry/pkg/v1/platform.go

@@ -0,0 +1,59 @@
+// Copyright 2018 Google LLC All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v1
+
+import (
+	"sort"
+)
+
+// Platform represents the target os/arch for an image.
+type Platform struct {
+	Architecture string   `json:"architecture"`
+	OS           string   `json:"os"`
+	OSVersion    string   `json:"os.version,omitempty"`
+	OSFeatures   []string `json:"os.features,omitempty"`
+	Variant      string   `json:"variant,omitempty"`
+	Features     []string `json:"features,omitempty"`
+}
+
+// Equals returns true if the given platform is semantically equivalent to this one.
+// The order of Features and OSFeatures is not important.
+func (p Platform) Equals(o Platform) bool {
+	return p.OS == o.OS && p.Architecture == o.Architecture && p.Variant == o.Variant && p.OSVersion == o.OSVersion &&
+		stringSliceEqualIgnoreOrder(p.OSFeatures, o.OSFeatures) && stringSliceEqualIgnoreOrder(p.Features, o.Features)
+}
+
+// stringSliceEqual compares 2 string slices and returns if their contents are identical.
+func stringSliceEqual(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i, elm := range a {
+		if elm != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+// stringSliceEqualIgnoreOrder compares 2 string slices and returns if their contents are identical, ignoring order
+func stringSliceEqualIgnoreOrder(a, b []string) bool {
+	a1, b1 := a[:], b[:]
+	if a1 != nil && b1 != nil {
+		sort.Strings(a1)
+		sort.Strings(b1)
+	}
+	return stringSliceEqual(a1, b1)
+}