install: Make shrinkwrap extraction work in 0.8

lib/fetch-package-metadata.js

@@ -253,6 +253,11 @@ function hasTarHeader (c) {
          c[264] === 0x00))
 }
 
+function dispose (stream) {
+  if (stream.destroy) return stream.destroy()
+  if (stream.close) return stream.close()
+}
+
 function untarStream (tarball, cb) {
   validate('SF', arguments)
   cb = once(cb)
@@ -273,7 +278,7 @@ function untarStream (tarball, cb) {
       doUntar()
     }
     else {
-      file.close()
+      dispose(file)
       var er = new Error('Non-gzip/tarball ' + tarball)
       er.code = 'ENOTTARBALL'
       return cb(er)
@@ -290,7 +295,7 @@ function untarStream (tarball, cb) {
       er.code = 'EGUNZIP'
       cb(er)
     })
-    tounpipe.push([stream, gunzip])
+    tounpipe.push(gunzip)
     stream = gunzip
     doUntar()
   }
@@ -302,18 +307,16 @@ function untarStream (tarball, cb) {
       er.code = 'EUNTAR'
       cb(er)
     })
-    tounpipe.push([stream, untar])
+    tounpipe.push(untar)
     stream = untar
     addClose()
   }
 
   function addClose() {
     stream.close = function () {
-      tounpipe.forEach(function (streams) {
-        streams[0].unpipe(streams[1])
-      })
+      tounpipe.forEach(dispose)
 
-      file.close()
+      dispose(file)
     }
   }
 }