Update file.php

Same fix like #3448 for Joomla 2.5.x
Change process flow

Fix process flow as noticed by @wilsonge on https://github.com/joomla/joomla-cms/pull/3448
[2.5] Backport #3454 against 2.5.x branche

See here for the orginal Tracker:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=33619&start=0
and here for the based pr aginast staging by @demis-palma:
https://github.com/joomla/joomla-cms/pull/3454
Merge pull request #3460 from zero-24/patch-14

[#33619] [2.5.x] Backport #3454 against 2.5.x branche
[cs] [33624] Expression is not assignable: Infix expression
Close #3466
Update en-GB.ini

Add missing language string for My Profile page help screen URL.

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_id=8103&tracker_item_id=33639
Merge pull request #3486 from Rajoz/patch-2

[#33639] Update en-GB.ini
Merge pull request #3449 from zero-24/patch-11

[#33614] Fix file.php in Joomla 2.5.x
[fix][#30747] FTP layer throwing error on update
Merge remote-tracking branch 'origin/2.5.x' into 2.5.x
Ignore the folder the build script creates for packages
Prepare 2.5.20 release
Prepare for 2.5.21 development
[imp] [33641] Add time unit in cache settings description
Close #3500
Install files
Update files
Merge branch 'patch_updatesversion_25' of https://github.com/piotr-cz/joomla-cms into patch_updatesversion_25