backport adaptive performance decals scaler

[odbb]

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Purpose of this PR

This adds Adaptive Performance decal scaler support.

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Testing status

Trunk PR: #6013

Manual Adaptive Performance tests - can be viewed in https://github.cds.internal.unity3d.com/unity/com.unity.adaptiveperformance/pull/118#

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Comments to reviewers

Requires https://github.cds.internal.unity3d.com/unity/com.unity.adaptiveperformance/pull/118# - only works when Adaptive Performance is installed.

[github-actions]

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[github-actions]

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Thank you!

[lukaschod]

awesome!

[simon-engelbrecht-soerensen]

lgtm