bug symfony#24494 [HttpFoundation] Add missing session.lazy_write config option (nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
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[HttpFoundation] Add missing session.lazy_write config option

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

See http://php.net/manual/en/session.configuration.php#ini.session.lazy-write

Commits
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dbc9a44 [HttpFoundation] Add missing session.lazy_write config option

Author: fabpot

src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php

@@ -76,6 +76,7 @@ class NativeSessionStorage implements SessionStorageInterface
      * gc_probability, "1"
      * hash_bits_per_character, "4"
      * hash_function, "0"
+     * lazy_write, "1"
      * name, "PHPSESSID"
      * referer_check, ""
      * serialize_handler, "php"
@@ -337,7 +338,7 @@ public function setOptions(array $options)
             'cookie_lifetime', 'cookie_path', 'cookie_secure',
             'entropy_file', 'entropy_length', 'gc_divisor',
             'gc_maxlifetime', 'gc_probability', 'hash_bits_per_character',
-            'hash_function', 'name', 'referer_check',
+            'hash_function', 'lazy_write', 'name', 'referer_check',
             'serialize_handler', 'use_strict_mode', 'use_cookies',
             'use_only_cookies', 'use_trans_sid', 'upload_progress.enabled',
             'upload_progress.cleanup', 'upload_progress.prefix', 'upload_progress.name',