[clang] [clang-format] Add IndentPPDirectives Leave option (PR #139750)

[via cfe-commits]

================
@@ -162,15 +162,17 @@ UnwrappedLineParser::UnwrappedLineParser(
       LangOpts(getFormattingLangOpts(Style)), Keywords(Keywords),
       CommentPragmasRegex(Style.CommentPragmas), Tokens(nullptr),
       Callback(Callback), AllTokens(Tokens), PPBranchLevel(-1),
-      IncludeGuard(Style.IndentPPDirectives == FormatStyle::PPDIS_None
+      IncludeGuard((Style.IndentPPDirectives == FormatStyle::PPDIS_None ||
+                    Style.IndentPPDirectives == FormatStyle::PPDIS_Leave)
----------------
owenca wrote:

```suggestion
      IncludeGuard(Style.IndentPPDirectives == FormatStyle::PPDIS_None ||
                           Style.IndentPPDirectives == FormatStyle::PPDIS_Leave
```

https://github.com/llvm/llvm-project/pull/139750