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

[via cfe-commits]

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@@ -49,6 +49,12 @@ enum class WarningScope {
   IntraTU  // For warnings on functions local to a Translation Unit.
 };
 
+struct LifetimeSafetyAliasChainEntry {
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iitianpushkar wrote:

Expr *E/*Call points the same call expression, so, i am thinking to make the following changes :
```cpp
struct LifetimeBoundInfo {
  const ParmVarDecl *Param = nullptr;
  bool IsImplicitObject = false;
};

struct LifetimeSafetyAliasChainEntry {
  const Expr *E = nullptr;
  std::optional<LifetimeBoundInfo> LifetimeBound;
};
```
Will this be a good idea for deduplication (atleast for Expr)  ?

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