[clang] [clang-tools-extra] [clang] improve class type sugar preservation in pointers to members (PR #130537)

[Matheus Izvekov via cfe-commits]

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@@ -13461,13 +13486,112 @@ static ElaboratedTypeKeyword getCommonTypeKeyword(const T *X, const T *Y) {
                                             : ElaboratedTypeKeyword::None;
 }
 
+static NestedNameSpecifier *getCommonNNS(ASTContext &Ctx,
+                                         NestedNameSpecifier *X,
+                                         NestedNameSpecifier *Y, bool Sugar) {
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mizvekov wrote:

`Sugar = true` means that we don't expect X and Y to be equivalent.

https://github.com/llvm/llvm-project/pull/130537