Shader Checker Layer: make sure iterated list is of non-zero length
Shader Checker Layer: make sure iterated list is of non-zero length

On MSVC++, need a check to make sure a list is of non-zero length
before attempting to iterate on it.

KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools,KhronosGroup/Vulkan-Tools