[HttpFoundation] Add ability to change JSON encoding options
feature #9915 [HttpFoundation] Add ability to change JSON encoding options (stloyd)

This PR was merged into the 2.5-dev branch.

Discussion
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[HttpFoundation] Add ability to change JSON encoding options

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Tests pass?   | yes
| Fixed tickets | #9086
| License       | MIT

Commits
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89f4784 [HttpFoundation] Add ability to change JSON encoding options