[clang] [LifetimeSafety] Introduce buildOriginFlowChain to use-after-invalidation (PR #208891)

[Gábor Horváth via cfe-commits]

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@@ -263,12 +263,16 @@ class LifetimeChecker {
         if (Warning.InvalidatedByExpr) {
           if (IssueExpr)
             // Use-after-invalidation of an object on stack.
-            SemaHelper->reportUseAfterInvalidation(IssueExpr, UF->getUseExpr(),
-                                                   Warning.InvalidatedByExpr);
+            SemaHelper->reportUseAfterInvalidation(
+                IssueExpr, UF->getUseExpr(), Warning.InvalidatedByExpr,
+                getExprChain(
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Xazax-hun wrote:

We have this repeated pattern of `getExprChain(LoanPropagation.buildOriginFlowChain(...))`. I am wondering if this means we would be better off with a helper that gives us directly the expression chain and would take one additional argument, the loan propagation.

https://github.com/llvm/llvm-project/pull/208891