Fix auto exposure flickering on the right eye

[fcoulombe]

Please read the Contributing guide before making a PR.

• Read the Graphics repository & Yamato FAQ.

Checklist for PR maker

• Have you added a backport label (if needed)? For example, the need-backport-* label. After you backport the PR, the label changes to backported-*.
• Have you updated the changelog? Each package has a CHANGELOG.md file.
• Have you updated or added the documentation for your PR? When you add a new feature, change a property name, or change the behavior of a feature, it's best practice to include related documentation changes in the same PR. If you do add documentation, make sure to add the relevant Graphics Docs team member as a reviewer of the PR. If you are not sure which person to add, see the Docs team contacts sheet.
• Have you added a graphic test for your PR (if needed)? When you add a new feature, or discover a bug that tests don't cover, please add a graphic test.

---

Purpose of this PR

Fix auto exposure flickering on the right eye https://fogbugz.unity3d.com/f/cases/1336238/
multipass mode renders with a single eye since it does it in two passes.
using xrActiveEye will ping pong between 0 and 1 but here we always want to pass 0 since we have a single eye.

---

Testing status

trunk, 2020.3.11f1, 2019.4.30f1
https://unity-ci.cds.internal.unity3d.com/job/9175200
https://unity-ci.cds.internal.unity3d.com/job/9175186
https://unity-ci.cds.internal.unity3d.com/job/9175557

---

Comments to reviewers

Notes for the reviewers you have assigned.

[fabien-unity]

LGTM

[mikesfbay]

Can you add a QA to verify (Jason or Ryan)? Otherwise, LGTM

[fcoulombe]

Hi @JasonCostanza can you help with testing to see if this fogbugz case is fixed, and there's no regressions with other postfx effects?

[JasonCostanza]

Hi @JasonCostanza can you help with testing to see if this fogbugz case is fixed, and there's no regressions with other postfx effects?

I'll get on this today or tomorrow if that's okay

[fcoulombe]

gentle ping on this

[JasonCostanza]

Ah, apologies fell off my radar. Putting a note on my monitor to not forget this! Flight Control was down for a while so I lost visibility on some PR's I was assigned, it's back up now

[JasonCostanza]

2022.1.0a12.1604
Revision: trunk 816252c3efbb
Built: Wed, 06 Oct 2021 17:58:29 GMT

commit 349d581 (HEAD -> xr/graphics/fix-autoexposure-flicker-right-eye, origin/xr/graph

Both eyes render equally on WMR HMD in play mode as described in the bug. LGTM

this seems to be blocking merge. dismissing since it's outdated