Refactor how GraphicsPipelineCongfigurator::compare() handles the shaderHints->defines and descriptorConfigurator->defines together to avoid failure to match compatible configurations.

[robertosfield]

No description provided.

[swp-ariaci]

This change appears to introduce a regression.

While testing the updated comparison logic, I ran into a crash in previously working code caused by dereferencing GraphicsPipelineConfigurator::descriptorConfigurator without a null check.

I’ve added a minimal reproducible example and details here:
#1682 (comment)

In short, descriptorConfigurator is accessed unconditionally in compare(), but it can be null in practice, which leads to a crash during SharedObjects::share(..., init).

It looks like a null check is needed before accessing it.