We can cut out some gratuitous inhertence as follows:
- `MixStoreDirMethods` -> `StoreDirConfig`
- `StoreDirConfig` deleted because no longer needed. It is just folded
into `StoreConfig`.
- `StoreDirConfigBase` -> `StoreConfigBase` same trick still needed, but
now is for `StoreConfig` not `StoreDirConfig`
Here's how we got here:
1. I once factored out `StoreDirConfig` in #6236.
2. I factored out `MixStoreDirMethods` in #13154.
But, I didn't realize at point (2) that we didn't need `StoreDirConfig`
anymore, all uses of `StoreDirConfig` could instead be uses of
`MixStoreDirMethods`. Now I am doing that, and renaming
`MixStoreDirMethods` to just `StoreDirConfig` to reduce churn.
I had not wanted to cause unncessary churn before, but now that we've
bitten the bullet with the Big Reformat, I feel it is the right time.
Future readers will appreciate that the declarations and definitions
files are one-to-one as they should be, and `store-api.cc` is good to
shrink in any event.
I don't think there are outstanding PRs changing this code either. (I
had some for a while, but they are all merged.)
* It is tough to contribute to a project that doesn't use a formatter,
* It is extra hard to contribute to a project which has configured the formatter, but ignores it for some files
* Code formatting makes it harder to hide obscure / weird bugs by accident or on purpose,
Let's rip the bandaid off?
Note that PRs currently in flight should be able to be merged relatively easily by applying `clang-format` to their tip prior to merge.
