framework/web/CookieCollection.php
public function remove($cookie, $removeFromBrowser = true)
    {
        if ($this->readOnly) {
            throw new InvalidCallException('The cookie collection is read only.');
        }
        if ($cookie instanceof Cookie) {
            $cookie->expire = 1;
            $cookie->value = '';
        } else {
            $cookie = Yii::createObject([
                'class' => 'yii\web\Cookie',
                'name' => $cookie,
                'expire' => 1,
            ]);
        }
        if ($removeFromBrowser) {
            $this->_cookies[$cookie->name] = $cookie;
        } else {
            unset($this->_cookies[$cookie->name]);
        }
    }
public function remove($cookie, $removeFromBrowser = true)
    {
        if ($this->readOnly) {
            throw new InvalidCallException('The cookie collection is read only.');
        }
        if ($cookie instanceof Cookie) {
            $cookie->expire = 1;
            $cookie->value = '';
        } else {
            $cookie = Yii::createObject([
                'class' => 'yii\web\Cookie',
                'name' => $cookie,
                'expire' => 1,
            ]);
        }
        if ($removeFromBrowser) {
            $this->_cookies[$cookie->name] = $cookie;
        } else {
            unset($this->_cookies[$cookie->name]);
        }
    }
Removes a cookie.
If `$removeFromBrowser` is true, the cookie will be removed from the browser.
In this case, a cookie with outdated expiry will be added to the collection.
@param Cookie|string $cookie the cookie object or the name of the cookie to be removed.
@param bool $removeFromBrowser whether to remove the cookie from browser
@throws InvalidCallException if the cookie collection is read only