[clang] Fixes and closes issues, #53390 and #58710. Added new controls to IndentNamespaceAliases, IndentUsingDeclarations and DecorateReflowedComments. (PR #102894)

[via cfe-commits]

mydeveloperday wrote:

> Hi @mydeveloperday, I will close this PR and correct it by making individual PRs for individual features.
> 
> Thankyou Rajkumar.

Incase this is your first submission here is some guidance for clang-format commits: (this isn't an exhaustive list)

- Get buy in from the main contributors @owenca , @HazardyKnusperkeks , @rymiel, @mydeveloperday before struggling through a large PR, we want to welcome new comers but we sort of need to have agreement on if we want the change.
- Always add tests 
- If you touch TokenAnnotator.cpp then likely you'll need an AnnotatorTest, but a formatting test is good
- We don't use lit tests much but 99% of the time we use the GoogleTests
- Try not to change existing tests
- Always git-clang-format the code before submission
- If you change Format.h you need to regenerate the documentation ClangStyleFormatOptions.rst every time
- Documentation needs to carry a /version when it was introduced if the option is new.
- New options need to carry /code examples
- Backwards compatibility is king! people get grump if we change default behavior.
- Ask yourself does this need a new option or can an existing option support what you need (maybe change it from bool -> enum)
- Begin all commits with [clang-format] in the title
- Adding the people above as reviewer helps your change get attention, some of us have lower cadence than the others (me), my day job gets in the way.
- We really want new features to have a public style guide for a largish open source project  that support the feature (not one or two people personal opinion), if you can quote the style guide wanting it that's extra points.
- Don't try and do more than one piece of work at a time.
- Don't change other pieces of code unrelated to your change (do that separately if its important)
- Run all the FormatTests before submitting (this times I've fat fingered that!)
- If you can run the sphinx documentation generation. (harder to setup)







https://github.com/llvm/llvm-project/pull/102894