Bug 1851535 - Remove folderPane.getFolderFromUri. r=aleca

This is unused. And a bit weird.

Differential Revision: https://phabricator.services.mozilla.com/D187527

--HG--
extra : moz-landing-system : lando

mail/base/content/about3Pane.js

@@ -2268,22 +2268,6 @@ var folderPane = {
     }
   },
 
-  /**
-   * Get the folder from the URI by looping through the list of folders and
-   * finding a matching URI.
-   *
-   * @param {string} uri
-   * @returns {?FolderTreeRow}
-   */
-  getFolderFromUri(uri) {
-    for (let folder of folderTree.querySelectorAll("li")) {
-      if (folder.uri == uri) {
-        return folder;
-      }
-    }
-    return [...folderTree.querySelectorAll("li")]?.find(f => f.uri == uri);
-  },
-
   /**
    * Called when a folder's new messages state changes.
    *