WebUI: show correct location path

The `path` might contains '&' (delimit character) so it must be
encoded.
Closes #15976.

src/webui/www/private/scripts/mocha-init.js

@@ -487,7 +487,7 @@ const initializeWindows = function() {
                 id: 'setLocationPage',
                 title: "QBT_TR(Set location)QBT_TR[CONTEXT=TransferListWidget]",
                 loadMethod: 'iframe',
-                contentURL: new URI("setlocation.html").setData("hashes", hashes.join('|')).setData("path", row.full_data.save_path).toString(),
+                contentURL: new URI("setlocation.html").setData("hashes", hashes.join('|')).setData("path", encodeURIComponent(row.full_data.save_path)).toString(),
                 scrollbars: false,
                 resizable: true,
                 maximizable: false,

src/webui/www/private/setlocation.html

@@ -31,16 +31,17 @@
 
         window.addEvent('domready', function() {
             const path = new URI().getData('path');
+
             // set text field to current value
             if (path)
-                $('setLocation').value = window.qBittorrent.Misc.escapeHtml(path);
+                $('setLocation').value = decodeURIComponent(path);
 
             $('setLocation').focus();
             $('setLocationButton').addEvent('click', function(e) {
                 new Event(e).stop();
                 // check field
                 const location = $('setLocation').value.trim();
-                if (location === null || location === "") {
+                if ((location === null) || (location === "")) {
                     $('error_div').set('text', 'QBT_TR(Save path is empty)QBT_TR[CONTEXT=TorrentsController]');
                     return false;
                 }