[NEXT_MAJOR] Remove `AbstractAdmin::validate` method and all validation-related methods.

[VincentLanglet]

As explained in the AdminInterface, the validate method doesn't work well (we have bug issue) and is useless since Symfony have his own form validation.

    /**
     * NEXT_MAJOR: remove this method.
     *
     * @param object $object
     *
     * @deprecated this feature cannot be stable, use a custom validator,
     *             the feature will be removed with Symfony 2.2
     */
    public function validate(ErrorElement $errorElement, $object);

I create this issue because we only added one NEXT_MAJOR comment but there is no real removal-plan, we'll have at least to:

• remove AbstractAdmin::attachInlineValidator.
• remove AbstractAdmin::validate.
• remove AbstractAdminExtension::validate.
• remove AdminExtensionInterface::validate.
• update the UPGRADE.md file.

We should also add a deprecation in 3.x.

[tambait]

@VincentLanglet When listed methods are removed, is there anything more to be done (for example is there need to add Symfony's ValidatorInterface somewhere)? I tried to search to see where validate methods are called throughout the code, SetObjectFieldValueAction uses ValidatorInterface and the rest is in the list you provided.

[VincentLanglet]

@VincentLanglet When listed methods are removed, is there anything more to be done (for example is there need to add Symfony's ValidatorInterface somewhere)? I tried to search to see where validate methods are called throughout the code, SetObjectFieldValueAction uses ValidatorInterface and the rest is in the list you provided.

We want to remove all the validation features from the Admin, so there is nothing to add.

I look at SetObjectFieldValueAction and we should keep it.

So it require to add in 3.x

/**
 * NEXT_MAJOR: Remove this methods.
 *
 * @deprecated since sonata-admin/admin-bundle 3.x
 */

In the interface for all the validate-related methods, with an upgrade note and to remove all these methods in master.

[tambait]

And what about defineFormBuilder method in AbstractAdmin it calls attachInlineValidator? I'll remove the line but not sure if any additional action on the method is needed.

[VincentLanglet]

Only the call $this->attachInlineValidator(); should be removed in defineFormBuilder