[clang-tools-extra] [clang-reorder-fields] Support designated initializers (PR #142150)

[Vladimir Vuksanovic via cfe-commits]

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@@ -81,18 +83,52 @@ getNewFieldsOrder(const RecordDecl *Definition,
   return NewFieldsOrder;
 }
 
+struct ReorderedStruct {
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vvuksanovic wrote:

Can you clarify what should I pull to a separate commit? I can create a new commit for the `ReorderedStruct` changes, before the designator changes. Should I move `addReplacement` changes there? The new overload would be unused in that commit.

https://github.com/llvm/llvm-project/pull/142150