refactor(core): remove withBody from public testing API

[mhevery]

No description provided.

[mary-poppins]

You can preview 8d497d5 at https://pr25171-8d497d5.ngbuilds.io/.

[mary-poppins]

You can preview db77353 at https://pr25171-db77353.ngbuilds.io/.

[mhevery]

http://test/OCL:206370143:BASE:206370250:1532725373752:b1d0e23e

[mary-poppins]

You can preview b5bb1cc at https://pr25171-b5bb1cc.ngbuilds.io/.

[ngbot]

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[angular-automatic-lock-bot]

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