minor symfony#8895 Mention the new behavior of dump() which returns the passed value (javiereguiluz)

This PR was merged into the 3.4 branch.

Discussion
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Mention the new behavior of dump() which returns the passed value

This fixes symfony#8459.

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0e871db Mention the new behavior of dump() which returns the passed value

Author: javiereguiluz

components/var_dumper.rst

@@ -50,6 +50,9 @@ For example::
 
     dump($someVar);
 
+    // dump() returns the passed value, so you can dump an object and keep using it
+    dump($someObject)->someMethod();
+
 By default, the output format and destination are selected based on your
 current PHP SAPI: