Bugfix: Context menu misplaced when triggered by keyboard navigation

We've fixed a bug where triggering the context menu by keyboard navigation misplaced the menu and made it inaccessible.

https://github.com/owncloud/web/pull/7230
https://github.com/owncloud/web/pull/7314
https://github.com/owncloud/web/pull/7386
https://github.com/owncloud/web/issues/7187
