minor symfony#17576 [YAML] Refine the return value of Yaml::parse() (jakzal)

This PR was merged into the 2.3 branch.

Discussion
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[YAML] Refine the return value of Yaml::parse()

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Commits
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6a806e3 [YAML] Refine the return value of Yaml::parse()

Author: fabpot

src/Symfony/Component/Yaml/Yaml.php

@@ -21,10 +21,7 @@
 class Yaml
 {
     /**
-     * Parses YAML into a PHP array.
-     *
-     * The parse method, when supplied with a YAML stream (string or file),
-     * will do its best to convert YAML in a file into a PHP array.
+     * Parses YAML into a PHP value.
      *
      *  Usage:
      *  <code>
@@ -40,7 +37,7 @@ class Yaml
      * @param bool   $exceptionOnInvalidType True if an exception must be thrown on invalid types false otherwise
      * @param bool   $objectSupport          True if object support is enabled, false otherwise
      *
-     * @return array The YAML converted to a PHP array
+     * @return mixed The YAML converted to a PHP value
      *
      * @throws ParseException If the YAML is not valid
      */