pub trait FormDataMethods {
// Required methods
fn Append(&self, name: USVString, value: USVString);
fn Append_(
&self,
name: USVString,
value: &Blob,
filename: Option<USVString>
);
fn Delete(&self, name: USVString);
fn Get(&self, name: USVString) -> Option<FileOrUSVString>;
fn GetAll(&self, name: USVString) -> Vec<FileOrUSVString>;
fn Has(&self, name: USVString) -> bool;
fn Set(&self, name: USVString, value: USVString);
fn Set_(&self, name: USVString, value: &Blob, filename: Option<USVString>);
}