Merge branch '2.7' into 2.8

* 2.7:
  Adding information about empty files sent using BinaryFileResponse.

components/http_foundation/introduction.rst

@@ -519,6 +519,13 @@ It is possible to delete the file after the request is sent with the
 :method:`Symfony\\Component\\HttpFoundation\\BinaryFileResponse::deleteFileAfterSend` method.
 Please note that this will not work when the ``X-Sendfile`` header is set.
 
+.. note::
+
+    If you *just* created the file during this same request, the file *may* be sent
+    without any content. This may be due to cached file stats that return zero for
+    the size of the file. To fix this issue, call ``clearstatcache(false, $file)``
+    with the path to the binary file.
+
 .. _component-http-foundation-json-response:
 
 Creating a JSON Response