[clang] [Lifetime Safety] Highlight lifetimebound calls in alias chain diagnostics (PR #206337)

[Gábor Horváth via cfe-commits]

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@@ -30,6 +31,11 @@ namespace clang::lifetimes::internal {
 
 using FactID = utils::ID<struct FactTag>;
 
+struct LifetimeBoundInfo {
+  const ParmVarDecl *Param = nullptr;
+  bool IsImplicitObject = false;
+};
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Xazax-hun wrote:

There are a couple ways around this. The rest of the analysis is sometimes using a `PointerUnion<ParmVarDecl*, CXXMethodDecl*>` and the declaration to the method represents the implicit object parameter. Alternative design is an optional pointer and empty optional meaning not found and a non-empty null meaning the implicit this. Just some random ideas, no strong preference. 

https://github.com/llvm/llvm-project/pull/206337