ASV Samples That Require Baked ShaderVariantAssets Must Check The Registry Key "O3DE/Atom/Shaders/BuildVariants"

[galibzon]

For the sake of iteration speed, sometimes engineers set the registry key "O3DE/Atom/Shaders/BuildVariants" to "False" and forget about it.
One day they run ASV Samples like "RHI/IndirectRendering" and the samples fail to run properly because the sample is waiting for some particular ShaderVariantAssets to be ready, but the OnShaderVariantReinitialized() notification never arrives. The engineer can struggle for hours because they forgot to set "O3DE/Atom/Shaders/BuildVariants" back to "True".

Solution:
All ASV Samples that require Baked ShaderVariantAssets must check if the registry key "O3DE/Atom/Shaders/BuildVariants" is enabled. If it is not enabled, then an explicit message should be presented to the user.

By default, the file: "\GIT\o3de\Gems\Atom\Asset\Shader\Registry\atom_shaders.setreg" has such key set to "True".

[galibzon]

@Adi-Amazon

[moudgils]

@galibzon close this if not applicable