[clang] [LifetimeSafety] Add multi-block support to buildOriginFlowChain (PR #204592)

[Gábor Horváth via cfe-commits]

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@@ -550,11 +550,25 @@ class LifetimeSafetySemaHelperImpl : public LifetimeSafetySemaHelper {
     return "expression";
   }
 
+  bool isInvalidExpr(const Expr *E) {
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Xazax-hun wrote:

I wonder if we need this function. Would `E == E->IgnoreImplicit()` be a viable test to see if we have an implicit node?

https://github.com/llvm/llvm-project/pull/204592