0.9 branch Undo button feature

[vidiecan]

Expected: "Undoes" latest action Result: Query failed: Syntax error at position 5. Please make sure the query and selected query type are correct.

The problems seems to be the following: Menu item is constructed as

        self.query_undo = (
            HideOnCustomCondItem(MainMenu.CONCORDANCE('undo'), _('Undo'), 'view')
            .add_args(
                ('q', self._args['undo_q']))
            .enable_if(lambda d: len(d.get('undo_q', [])) > 0)
        )

when you mouseover the menu item the following code is executed

_createLink: function _createLink() {
                if (this.props.data.url) {
                    return this.props.data.url;
                } else if (this.props.data.action && typeof this.props.data.args === 'string') {
                    return this.createActionLink(this.props.data.action + '?' + this.props.data.args);
                } else if (this.props.data.action) {
                    return this.createActionLink(this.props.data.action, this.props.data.args);
                }
                return undefined;
            },

which creates url from e.g.,

this.props.data.action = "view"
this.props.data.args = Array(2) ("q", "q=aword%2C%5Blc%3D%22p%C5%99edem%22%5D")

like this

> http://localhost:5000/view?q=q%3Daword%252C%255Blc%253D%2522p%25C5%2599edem%2522%255D

(which is already strange because of all the other parameters from the original url).

This gets into python as

<type 'tuple'>: (u'q=aword%2C%5Blc%3D%22p%C5%99edem%22%5D',)

which ends with an expected exception

Query failed: Syntax error at position 5.