exception listener, allow easier overloading of the default behavior
merged branch mevers47/master (PR #7021)

This PR was submitted for the master branch but it was merged into the 2.2 branch instead (closes #7021).

Commits
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c9c1ce6 [HttpKernel] exception listener, allow easier overloading of the default behavior

Discussion
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[HttpKernel] exception listener, allow easier overloading of the default behavior

Hi Fabien,

This commit you wrote about a month ago helped me to overload the 'logException' method:
https://github.com/symfony/symfony/commit/1a6c9b31438e45180001957bb64f97d1cf54ca4f

Because the logger property was private I could not access it from the subclass. This PR changes both properties: controller and logger from private to public members. So they can be used from 'logException'.
[HttpFoundation] fixed, overwritten CONTENT_TYPE