Merge branch '2.3' into 2.7

Conflicts:
	book/security.rst

Author: wouterj

book/security.rst

@@ -1220,6 +1220,12 @@ is defined by the ``target`` parameter above (e.g. the ``homepage``).
 Dynamically Encoding a Password
 -------------------------------
 
+.. note::
+
+    For historical reasons, Symfony uses the term *"password encoding"* when it
+    should really refer to *"password hashing"*. The "encoders" are in fact
+    `cryptographic hash functions`_.
+
 If, for example, you're storing users in the database, you'll need to encode
 the users' passwords before inserting them. No matter what algorithm you
 configure for your user object, the hashed password can always be determined
@@ -1428,5 +1434,6 @@ Learn More from the Cookbook
 
 .. _`frameworkextrabundle documentation`: https://symfony.com/doc/current/bundles/SensioFrameworkExtraBundle/index.html
 .. _`security advisories database`: https://github.com/FriendsOfPHP/security-advisories
+.. _`cryptographic hash functions`: https://en.wikipedia.org/wiki/Cryptographic_hash_function
 .. _`HWIOAuthBundle`: https://github.com/hwi/HWIOAuthBundle
 .. _`SensioDistributionBundle`: https://packagist.org/packages/sensio/distribution-bundle

reference/forms/types/entity.rst

@@ -181,14 +181,15 @@ instead of the ``default`` entity manager.
 query_builder
 ~~~~~~~~~~~~~
 
-**type**: ``Doctrine\ORM\QueryBuilder`` or a Closure
+**type**: ``Doctrine\ORM\QueryBuilder`` or a Closure **default**: ``null``
 
 Allows you to create a custom query for your choices. See
 :ref:`ref-form-entity-query-builder` for an example.
 
-The value of this option can either be a ``QueryBuilder`` object or a Closure.
-When using a Closure, you will be passed the ``EntityRepository`` of the entity
-as the only argument and should return a ``QueryBuilder``.
+The value of this option can either be a ``QueryBuilder`` object, a Closure or
+``null`` (which will load all entities). When using a Closure, you will be
+passed the ``EntityRepository`` of the entity as the only argument and should
+return a ``QueryBuilder``.
 
 Overridden Options
 ------------------