[clang] [analyzer] Introduce the invalidation artifact symbol (PR #207155)

[Gábor Horváth via cfe-commits]

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@@ -126,6 +126,16 @@ class SValExplainer : public FullSValVisitor<SValExplainer, std::string> {
            printCFGElementRef(S->getCFGElementRef()) + "'";
   }
 
+  std::string
+  VisitSymbolInvalidationArtifact(const SymbolInvalidationArtifact *S) {
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Xazax-hun wrote:

Bikeshedding: I wonder where the InvalidationArtifact name comes from. If we follow the naming convention of `ConjuredSymbol`, I wonder if this should simply be `InvalidatedSymbol` or `SymbolAfterInvalidation`. 

https://github.com/llvm/llvm-project/pull/207155