Reproduction steps:
1. Create an empty Unity Project
2. Using the Package Manager, install Core RP Library and Visual Effect Graph
3. Wait for the Packages to download and for Unity to recompile

Expected: after recompiling Unity does not throw any warnings
Actual: after recompiling Unity throws warnings regarding Visual Effect Graph

Reproduces on: Unity Version 2018.3.12f1 and Package Version 4.10.0-preview
Does not reproduce on: Unity Version 2019.1.0b9, 2019.2.0a10 and Package Version 5.10.0-preview

Note:
- Visual Effect Graph version 5.10.0 is not available on Unity Version 2018.3.12f1
- Warnings:
Library\PackageCache\com.unity.visualeffectgraph@4.10.0-preview\Editor\Models\Operators\Implementations\ChangeSpace.cs(12,28): warning CS0649: Field 'ChangeSpace.m_targetSpace' is never assigned to, and will always have its default value
Library\PackageCache\com.unity.visualeffectgraph@4.10.0-preview\Runtime\Utilities\Playables\VisualEffectActivation\VisualEffectActivationBehaviour.cs(39,26): warning CS0649: Field 'VisualEffectActivationBehaviour.clipExitEventAttributes' is never assigned to, and will always have its default value null
Library\PackageCache\com.unity.visualeffectgraph@4.10.0-preview\Runtime\Utilities\Playables\VisualEffectActivation\VisualEffectActivationBehaviour.cs(37,26): warning CS0649: Field 'VisualEffectActivationBehaviour.clipEnterEventAttributes' is never assigned to, and will always have its default value null