[clang] [clang-format] Add an option to control indentation of `export { ... }` (PR #110381)

[Björn Schäpers via cfe-commits]

================
@@ -171,6 +171,8 @@ class UnwrappedLineParser {
   void parseRequiresClause(FormatToken *RequiresToken);
   void parseRequiresExpression(FormatToken *RequiresToken);
   void parseConstraintExpression();
+  void parseCXXExportBlock();
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HazardyKnusperkeks wrote:

```suggestion
  void parseCppExportBlock();
```
This would be more consistent.

https://github.com/llvm/llvm-project/pull/110381