Updated `get_current_values` function to not include undefined keys
in current_values object and if the input field is of type file and
a file is selected then set the value equal to file object.
The new update_submit_disabled_state_on_change parameter configures
the dialog_widget system to disable/enable the confirmation button
depending on whether any of the fields in the modal have values
differing from their initial values.
Fixes#22683.
Changes `AjaxRequest` name to more clear one `AjaxRequestHandler`,
also moved this type to `types.ts` with a comment to move it into
`channel.js` once it migrates to typescript.
Created `WidgetConfig` type which has all the parameter that can be
passed launch(). Except html_heading, html_body, and on_click all
other fields are optional. Therefore, removed checking of undefined
mandatory fields as it will be done by typescript.
Co-authored-by: Hardik Dharmani <Ddharmani99@gmail.com>
