[VOL-4289]  Proto changes for gRPC migration

Change-Id: I317a0a865ccf78d0c37aa229c50d293a3f66c8bb
diff --git a/vendor/google.golang.org/grpc/internal/grpcutil/target.go b/vendor/google.golang.org/grpc/internal/grpcutil/target.go
new file mode 100644
index 0000000..8833021
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/grpcutil/target.go
@@ -0,0 +1,89 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * 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 grpcutil provides a bunch of utility functions to be used across the
+// gRPC codebase.
+package grpcutil
+
+import (
+	"strings"
+
+	"google.golang.org/grpc/resolver"
+)
+
+// split2 returns the values from strings.SplitN(s, sep, 2).
+// If sep is not found, it returns ("", "", false) instead.
+func split2(s, sep string) (string, string, bool) {
+	spl := strings.SplitN(s, sep, 2)
+	if len(spl) < 2 {
+		return "", "", false
+	}
+	return spl[0], spl[1], true
+}
+
+// ParseTarget splits target into a resolver.Target struct containing scheme,
+// authority and endpoint. skipUnixColonParsing indicates that the parse should
+// not parse "unix:[path]" cases. This should be true in cases where a custom
+// dialer is present, to prevent a behavior change.
+//
+// If target is not a valid scheme://authority/endpoint as specified in
+// https://github.com/grpc/grpc/blob/master/doc/naming.md,
+// it returns {Endpoint: target}.
+func ParseTarget(target string, skipUnixColonParsing bool) (ret resolver.Target) {
+	var ok bool
+	if strings.HasPrefix(target, "unix-abstract:") {
+		if strings.HasPrefix(target, "unix-abstract://") {
+			// Maybe, with Authority specified, try to parse it
+			var remain string
+			ret.Scheme, remain, _ = split2(target, "://")
+			ret.Authority, ret.Endpoint, ok = split2(remain, "/")
+			if !ok {
+				// No Authority, add the "//" back
+				ret.Endpoint = "//" + remain
+			} else {
+				// Found Authority, add the "/" back
+				ret.Endpoint = "/" + ret.Endpoint
+			}
+		} else {
+			// Without Authority specified, split target on ":"
+			ret.Scheme, ret.Endpoint, _ = split2(target, ":")
+		}
+		return ret
+	}
+	ret.Scheme, ret.Endpoint, ok = split2(target, "://")
+	if !ok {
+		if strings.HasPrefix(target, "unix:") && !skipUnixColonParsing {
+			// Handle the "unix:[local/path]" and "unix:[/absolute/path]" cases,
+			// because splitting on :// only handles the
+			// "unix://[/absolute/path]" case. Only handle if the dialer is nil,
+			// to avoid a behavior change with custom dialers.
+			return resolver.Target{Scheme: "unix", Endpoint: target[len("unix:"):]}
+		}
+		return resolver.Target{Endpoint: target}
+	}
+	ret.Authority, ret.Endpoint, ok = split2(ret.Endpoint, "/")
+	if !ok {
+		return resolver.Target{Endpoint: target}
+	}
+	if ret.Scheme == "unix" {
+		// Add the "/" back in the unix case, so the unix resolver receives the
+		// actual endpoint in the "unix://[/absolute/path]" case.
+		ret.Endpoint = "/" + ret.Endpoint
+	}
+	return ret
+}