minor symfony#9913 Mistake in http_foundation.rst (vuras)

This PR was merged into the 4.1 branch.

Discussion
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Mistake in http_foundation.rst

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Commits
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acd02c8 Update http_foundation.rst

Author: javiereguiluz

components/http_foundation.rst

@@ -271,7 +271,7 @@ this complexity and defines some methods for the most common tasks::
 
     // Joins an associative array into a string for use in an HTTP header
     HeaderUtils::toString(array('foo' => 'abc', 'bar' => true, 'baz' => 'a b c'), ',')
-    // => 'foo=bar, baz, baz="a b c"'
+    // => 'foo=abc, bar, baz="a b c"'
 
     // Encodes a string as a quoted string, if necessary
     HeaderUtils::quote('foo "bar"')