twitter: revert 98a73d966d; it changed its imported root structure

I failed to catch that in review.

Change-Id: Ie88298a2f34595b27c6f98af6f31b61a29ebac1b

pkg/importer/twitter/twitter.go

@@ -187,12 +187,6 @@ func (im *imp) Run(ctx *importer.RunContext) error {
 		},
 	}
 
-	rootNode := r.RootNode()
-	if rootNode.Attr(nodeattr.Title) == "" {
-		screenName := acctNode.Attr(importer.AcctAttrUserName)
-		rootNode.SetAttr(nodeattr.Title, fmt.Sprintf("%s's Tweets", screenName))
-	}
-
 	userID := acctNode.Attr(importer.AcctAttrUserID)
 	if userID == "" {
 		return errors.New("UserID hasn't been set by account setup.")
@@ -253,7 +247,11 @@ func (r *run) importTweets(userID string) error {
 	maxId := ""
 	continueRequests := true
 
-	tweetsNode := r.RootNode()
+	tweetsNode, err := r.getTopLevelNode("tweets", "Tweets")
+	if err != nil {
+		return err
+	}
+
 	numTweets := 0
 	sawTweet := map[string]bool{}
 
@@ -355,7 +353,10 @@ func tweetsFromZipFile(zf *zip.File) (tweets []*zipTweetItem, err error) {
 func (r *run) importTweetsFromZip(userID string, zr *zip.Reader) error {
 	log.Printf("Processing zip file with %d files", len(zr.File))
 
-	tweetsNode := r.RootNode()
+	tweetsNode, err := r.getTopLevelNode("tweets", "Tweets")
+	if err != nil {
+		return err
+	}
 
 	var (
 		gate = syncutil.NewGate(tweetsAtOnce)
@@ -382,7 +383,7 @@ func (r *run) importTweetsFromZip(userID string, zr *zip.Reader) error {
 			})
 		}
 	}
-	err := grp.Err()
+	err = grp.Err()
 	log.Printf("zip import of tweets: %d total, err = %v", total, err)
 	return err
 }
@@ -498,6 +499,17 @@ func (r *run) importTweet(parent *importer.Object, tweet tweetItem, viaAPI bool)
 	return !changes, err
 }
 
+func (r *run) getTopLevelNode(path string, title string) (*importer.Object, error) {
+	tweets, err := r.RootNode().ChildPathObject(path)
+	if err != nil {
+		return nil, err
+	}
+	if err := tweets.SetAttr("title", title); err != nil {
+		return nil, err
+	}
+	return tweets, nil
+}
+
 // TODO(mpl): move to an api.go when we it gets bigger.
 
 type userInfo struct {