Mirror resolution does not change without a restart.

[Geenz]

Environment

Second Life Test 7.1.6.241011703 (64bit)

Description

Changing the mirror resolution at runtime does not apply without restarting the viewer.

Reproduction steps

1. Stand in front of a mirror with mirrors enabled.
2. Change the RenderHeroProbeResolution debug setting.
3. Note that the resolution does not change.

[sergiiiproductengine]

Passed QA.

Verified on the Second Life Release 7.1.8.9103842320 (64bit) on Win10/OSX in the scope of https://github.com/secondlife/iqa/issues/239.