close #7024

Fixed wrong Content-Length header when sending file using Response::sendContentAsFile().

Fixes #6852: Added `yii\helpers\BaseHtmlPurifier::helpers()` in order to be able to configure `HtmlPurifier` helper globally via subclassing

Makes it possible for classes that extend yii\web\ErrorHandler to provide their own informational URLs for types/classes/methods.

Fixes #6969: `yii\helpers\ArrayHelper::htmlEncode()` and `htmlDecode()` should not remove non-string data

fixes #6896

close #6913

fixes #6936

Translated messages in [[i18n\Formatter.php]]

Fixes #6661: Hyperlinks that are enclosed within an exist form will use the same form for submission if they specify both of the `href` and `data-method` attributes

TimeStampBehavior PHPDoc update for the `touch()` method

Fixes #5663 and #5671: Added support for using `data-params` to specify additional form data to be submitted via the `data-method` approach

fixes #yiisoft/yii#3712

- Made yii\web\Request::getQueryParam() and getBodyParam()'s doc blocks more consistent with each other
- getQueryParam() was incorrectly stating that if $name was omitted, all of $_GET would be returned (but $name is required)

Fixes #6697: Added `yii\helpers\Url::current()` method that allows adding or removing parameters from current URL

Fixes #5690: adjusted paths in message config generated by `yii message/config` to reflect directory structure better

Add mimeTypes Arabic validation message

ensure PDO instance has been created at this point