28e57f58b1
- Use specified default value in struct tags when binding a request input to struct for validation, even if sent empty, not only when not sent at all. - Add string field to `TestMappingDefault` test case. - Add test case for not sent form field to default to the value specified via code. - Add test case for form field sent empty to default to the value specified via code. Fixes: How to apply default value if empty value provided by client during model binding? #4042, #13042df, #a41721a