Steps to reproduce:

1) Open Unity hub and create a new LWRP template project
2) Go to Window >> Package Manager and Update LWRP package to 6.5.3
3) Go to Player Settings and change color pace form Linear to Gamma

Observe: LWRP shader errors and pink sene (check attached image "bug.png"):

Shader error in 'Hidden/Lightweight Render Pipeline/CopyDepth': failed to open source file: 'Packages/com.unity.render-pipelines.lightweight/Shaders/Utils/CopyDepthPass.hlsl' at line 21 (on d3d11)
Shader error in 'Paint1G_WAnim_Shader': failed to open source file: 'Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl' at line 71 (on d3d11)
Shader error in 'Paint1G_WAnim_Shader': failed to open source file: 'Packages/com.unity.render-pipelines.lightweight/ShaderLibrary/ShaderGraphFunctions.hlsl' at line 445 (on d3d11)
Shader error in 'Lightweight Render Pipeline/Lit': failed to open source file: 'LitForwardPass.hlsl' at line 122 (on d3d11)

Reproduced with:
2019.2.0b2, 2019.3.0a3
LWRP package version 6.5.3

Not reproduced with:
2019.2.0b2, 2019.3.0a3
LWRP package version 6.5.2

Regression since:
LWRP 6.5.3