Exposure Is More Extreme In High-End Mobile Preview Modes

In high-end mobile preview modes the exposure will return much more exaggerated results. This is related to the new default tone mapper settings since changing r.TonemapperFilm to 0 solves the issue.

1. Open a blank project
2. Change the exposure to "fixed at log +1 = Brightness 2x"
3. Change the preview rending level to iOS Metal Preview

RESULT
The scene gets noticeably brighter

EXPECTED
The exposure remains somewhat consistent between rendering previews.

Exposure is broken with iOs metal preview