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

[Gábor Horváth via cfe-commits]

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@@ -131,24 +131,37 @@ class ExpireFact : public Fact {
 };
 
 class OriginFlowFact : public Fact {
+public:
+  struct LifetimeBoundInfo {
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Xazax-hun wrote:

I wonder if it is a good idea to double the size of `OriginFlowFact` like this. We have a lot of flows, only a fraction of them results from `lifetimebound` annotations. An alternative design could be having this information on the side, in a `DenseMap<OriginFlowFact*, LifetimeBoundInfo>` that could be propagated during fact generation and consulted later on during reporting. 

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