remove part about adding extension

tuanalumi · xabbuh · commit 33446d1f4ca3 · 2018-04-09T14:42:41.000+02:00
I do not really understand this paragraph and did not follow it, but the `constraints` option still works. So I believe it is something historical.
diff --git a/validation.rst b/validation.rst
@@ -509,14 +509,6 @@ of the form fields::
         ;
     }
 
-The ``constraints`` option is only available if the ``ValidatorExtension``
-was enabled through the form factory builder::
-
-    Forms::createFormFactoryBuilder()
-        ->addExtension(new ValidatorExtension(Validation::createValidator()))
-        ->getFormFactory()
-    ;
-
 .. index::
    single: Validation; Constraint targets
 

Original file line number	Diff line number	Diff line change
`@@ -509,14 +509,6 @@ of the form fields::`
`509`	`509`	`;`
`510`	`510`	`}`
`511`	`511`
`512`		-The ``constraints`` option is only available if the ``ValidatorExtension``
`513`		`-was enabled through the form factory builder::`
`514`		`-`
`515`		`- Forms::createFormFactoryBuilder()`
`516`		`- ->addExtension(new ValidatorExtension(Validation::createValidator()))`
`517`		`- ->getFormFactory()`
`518`		`- ;`
`519`		`-`
`520`	`512`	`.. index::`
`521`	`513`	`single: Validation; Constraint targets`
`522`	`514`