[HttpFoundation] UploadedFile - moved a security check

Squashed commit of the following:

commit b03b32ecc985c4a4f9dc7df2d3336a4cd75aae30
Merge: fb7004b fc70e13
Author: Bilal Amarni <bilal.amarni@gmail.com>
Date:   Wed Feb 27 11:33:37 2013 +0100

    [HttpFoundation] UploadedFile - moved a security check

commit fc70e138c1d3858775c9efe51268cae6d7ec3f69
Author: Bilal Amarni <bilal.amarni@gmail.com>
Date:   Thu Jan 24 11:07:29 2013 +0100

    explicitly passed UPLOAD_ERR_OK constant in a test

commit dda03a2faab9539ca3a93736dd2bc0ec27feb4e7
Author: Bilal Amarni <bilal.amarni@gmail.com>
Date:   Fri Jan 18 17:24:06 2013 +0100

    [HttpFoundation] UploadedFile - moved a security check from move() to isValid()
merged branch bamarni/http-uploaded-file (PR #7201)

This PR was merged into the master branch.

Discussion
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[2.3] moved a security check in HttpUploadedFile

closes #6802

- [x] fix the testsuite, I've only run the component suite, but it needs to be updated in other places too (according to travis)

Commits
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5bb44f5 [HttpFoundation] UploadedFile - moved a security check
[HttpFoundation] added missing entry in the CHANGELOG