Update vendor dependencies

Change-Id: I3b1ca9f2687388c831d9d46a4e1de413ffae06ac

vendor/github.com/karrick/godirwalk/withoutNamlen.go

@@ -0,0 +1,36 @@
+// +build nacl linux solaris
+
+package godirwalk
+
+import (
+	"bytes"
+	"reflect"
+	"syscall"
+	"unsafe"
+)
+
+func nameFromDirent(de *syscall.Dirent) []byte {
+	// Because this GOOS' syscall.Dirent does not provide a field that specifies
+	// the name length, this function must first calculate the max possible name
+	// length, and then search for the NULL byte.
+	ml := int(uint64(de.Reclen) - uint64(unsafe.Offsetof(syscall.Dirent{}.Name)))
+
+	// Convert syscall.Dirent.Name, which is array of int8, to []byte, by
+	// overwriting Cap, Len, and Data slice header fields to values from
+	// syscall.Dirent fields. Setting the Cap, Len, and Data field values for
+	// the slice header modifies what the slice header points to, and in this
+	// case, the name buffer.
+	var name []byte
+	sh := (*reflect.SliceHeader)(unsafe.Pointer(&name))
+	sh.Cap = ml
+	sh.Len = ml
+	sh.Data = uintptr(unsafe.Pointer(&de.Name[0]))
+
+	if index := bytes.IndexByte(name, 0); index >= 0 {
+		// Found NULL byte; set slice's cap and len accordingly.
+		sh.Cap = index
+		sh.Len = index
+	}
+
+	return name
+}