[clang] [WIP] [Modules] Delay reading type source info of the preferred_name attribute. (PR #122250)

[Viktoriia Bakalova via cfe-commits]

VitaNuo wrote:

> The code in https://github.com/llvm/llvm-project/pull/122726 looks better. I didn't do detailed review since it is marked WIP.

Thanks for the feedback. I will then try to generalize https://github.com/llvm/llvm-project/pull/122726 to delay all/multiple attributes.  Depending on how that plays out, I will then send out https://github.com/llvm/llvm-project/pull/122726 for proper review.

https://github.com/llvm/llvm-project/pull/122250