bug #4758 [Components][Yaml] don't describe removed usage of Yaml::parse() (xabbuh)

This PR was merged into the master branch.

Discussion
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[Components][Yaml] don't describe removed usage of Yaml::parse()

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no (but related to symfony/symfony#13129)
| Applies to    | 3.0+
| Fixed tickets |

Commits
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d33b78b don't describe removed usage of Yaml::parse()

Author: wouterj

components/yaml/introduction.rst

@@ -138,12 +138,6 @@ string or a file containing YAML. Internally, it calls the
 :method:`Symfony\\Component\\Yaml\\Parser::parse` method, but enhances the
 error if something goes wrong by adding the filename to the message.
 
-.. caution::
-
-    Because it is currently possible to pass a filename to this method, you
-    must validate the input first. Passing a filename is deprecated in
-    Symfony 2.2, and will be removed in Symfony 3.0.
-
 .. _components-yaml-dump:
 
 Writing YAML Files