Fix ViewMode related bugs:

- The user will no longer lost their 'ViewMode' option after being updated in the settings.
- The console will not output errors due tot he scroll function when Mosaic mode is on.


Former-commit-id: 97aa6abdc8b864dc7a55dbf03a2e58895ea7613f [formerly ff9e6ff0898f32bd106b644b2e9002b5de45281c] [formerly 556cc12bd5ff1d91776c81f48dd1dceb8bb627b4 [formerly 51104c5ee70710b434ab42c58f738ecdce548fe6]]
Former-commit-id: dd63b2b818a7bd4960a7243866d6b2829f4c03a8 [formerly 45855d70eaa9a2b060d3a89cb70388040ea8e6d9]
Former-commit-id: 6e0ebf10d7fe3e2c234abc9c0ffd447cfbdd7455

http/download.go

@@ -17,21 +17,13 @@ import (
 // downloadHandler creates an archive in one of the supported formats (zip, tar,
 // tar.gz or tar.bz2) and sends it to be downloaded.
 func downloadHandler(c *fm.Context, w http.ResponseWriter, r *http.Request) (int, error) {
-	query := r.URL.Query().Get("format")
-
 	// If the file isn't a directory, serve it using http.ServeFile. We display it
 	// inline if it is requested.
 	if !c.File.IsDir {
-		if r.URL.Query().Get("inline") == "true" {
-			w.Header().Set("Content-Disposition", "inline")
-		} else {
-			w.Header().Set("Content-Disposition", "attachment; filename=\""+c.File.Name+"\"")
-		}
-
-		http.ServeFile(w, r, c.File.Path)
-		return 0, nil
+		return downloadFileHandler(c, w, r)
 	}
 
+	query := r.URL.Query().Get("format")
 	files := []string{}
 	names := strings.Split(r.URL.Query().Get("files"), ",")
 
@@ -111,3 +103,14 @@ func downloadHandler(c *fm.Context, w http.ResponseWriter, r *http.Request) (int
 	_, err = io.Copy(w, file)
 	return 0, err
 }
+
+func downloadFileHandler(c *fm.Context, w http.ResponseWriter, r *http.Request) (int, error) {
+	if r.URL.Query().Get("inline") == "true" {
+		w.Header().Set("Content-Disposition", "inline")
+	} else {
+		w.Header().Set("Content-Disposition", "attachment; filename=\""+c.File.Name+"\"")
+	}
+
+	http.ServeFile(w, r, c.File.Path)
+	return 0, nil
+}