Particle Systems Feed Boroken Values to Dynamic Parameters in Materials with Instanced Stereo Enabled

Working as expected in 4.21 CL# 4753647

Found in 4.22 CL# 7053642, 4.23 Preview 1 CL# 7236301, and 4.24 CL# 7173985

This is a regression


Additional Notes:
-This doesn't occur when you set the Spawn rate to 1.
-If you hook up a DebugScalarValues node to look at the values, you'll see that the Parameter is randomly returning numbers.
-The higher the spawn rate, the higher the deviation in values.

Steps to Reproduce
  1. Open the Editor
  2. Enable Instanced Stereo
  3. Create a Material that is Surface > Opaque > Unlit
  4. Add a Dynamic Parameter node and plug Param1 into emissive
  5. Create a mesh particle system and override the material with the one created
  6. Place the particle in the level
  7. Play in VR Preview

Steps with attached Project:

  1. Open the attached proejct
  2. Play in VR Preview

The particle will flicker 

No filcker would occur

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ComponentRendering - Cascade
Affects Versions4.
Target Fix4.24
Fix Commit7848620
Main Commit8980992
Release Commit9552237
CreatedJul 11, 2019
ResolvedAug 7, 2019
UpdatedOct 28, 2019