[clang] [clang-format] Add option AllowShortRecordOnASingleLine (PR #154580)

[Tomáš Slanina via cfe-commits]

itzexpoexpo wrote:

Wouldn't this be the correct behavior though? Since records are a subset of blocks, it feels like it should override the blocks option, letting it be the catch-all and `...Record...` an exception.

Although looking at `tryMergeSimpleBlock`, the option already overrides `AllowShortFunctions...`, so I'm probably missing something?

https://github.com/llvm/llvm-project/pull/154580