[VarDumper] add meta-data on hover

Author: nicolas-grekas

Tests/DataCollector/DumpDataCollectorTest.php

@@ -49,7 +49,7 @@ public function testDump()
         $this->assertSame($xDump, $dump);
 
         $this->assertStringStartsWith(
-            'a:1:{i:0;a:5:{s:4:"data";O:39:"Symfony\Component\VarDumper\Cloner\Data":3:{s:45:"Symfony\Component\VarDumper\Cloner\Datadata";a:1:{i:0;a:1:{i:0;i:123;}}s:49:"Symfony\Component\VarDumper\Cloner\DatamaxDepth";i:-1;s:57:"Symfony\Component\VarDumper\Cloner\DatamaxItemsPerDepth";i:-1;}s:4:"name";s:25:"DumpDataCollectorTest.php";s:4:"file";s:',
+            'a:1:{i:0;a:5:{s:4:"data";O:39:"Symfony\Component\VarDumper\Cloner\Data":4:{s:45:"Symfony\Component\VarDumper\Cloner\Datadata";a:1:{i:0;a:1:{i:0;i:123;}}s:49:"Symfony\Component\VarDumper\Cloner\DatamaxDepth";i:-1;s:57:"Symfony\Component\VarDumper\Cloner\DatamaxItemsPerDepth";i:-1;s:54:"Symfony\Component\VarDumper\Cloner\DatauseRefHandles";i:-1;}s:4:"name";s:25:"DumpDataCollectorTest.php";s:4:"file";s:',
             str_replace("\0", '', $collector->serialize())
         );