[BUGFIX] Change submit handling of RsaEncryptionModule

Stores the original submit handler, remove it from the form element and
add it back only at a later point, when the RSA module wants to submit
the form. This prevents Chrome to submit a form twice if it contains a
RSA password protected field.

Resolves: #69713
Releases: master
Change-Id: I085b68dfeb901be960096e3d570da097adf0327b
Reviewed-on: http://review.typo3.org/43239


Reviewed-by: Stephan Großberndt <stephan@grossberndt.de>
Tested-by: Stephan Großberndt <stephan@grossberndt.de>
Reviewed-by: Nicole Cordes <typo3@cordes.co>
Tested-by: Nicole Cordes <typo3@cordes.co>
Reviewed-by: Mathias Brodala <mbrodala@pagemachine.de>