Added return type to Stopwatch::getSections()
minor #11067 [Stopwatch] Added return type to Stopwatch::getSections() (umpirsky)

This PR was merged into the 2.6-dev branch.

Discussion
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[Stopwatch] Added return type to Stopwatch::getSections()

https://github.com/symfony/symfony/pull/10851#discussion_r13479016

Commits
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ab00361 Added return type to Stopwatch::getSections()
[Debug] Symfony debug extension
[Debug] a README for the debug extension
[VarDumper] algo to clone any PHP variable to a breadth-first queue
[VarDumper] symfony_debug ext. fast and memory efficient cloning algo
[VarDumper] add casters for per class/resource custom state extraction
[VarDumper] casters for exceptions representation
[VarDumper] casters for SPL data structures
[VarDumper] Add workaround to https://bugs.php.net/65967
[VarDumper] casters for PDO related objects
[VarDumper] casters for removing the entity manager from Doctrine proxies
[VarDumper] interface for dumping collected variables
[VarDumper] CLI dedicated dumper and related abstract
[VarDumper] HTML variant of the CLI dumper
[VarDumper] spec for json based representation of PHP vars
[VarDumper] json dumper for interoperable displaying
[VarDumper] tests for JsonDumper
[VarDumper] tests for CliDumper
[VarDumper] README, LICENSE and composer.json