[clang] [Clang][analyzer] replace Stmt* with ConstCFGElementRef in SymbolConjured (PR #128251)

[Gábor Horváth via cfe-commits]

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@@ -101,8 +103,10 @@ class SymbolConjured : public SymbolData {
   }
 
 public:
-  /// It might return null.
-  const Stmt *getStmt() const { return S; }
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Xazax-hun wrote:

Would it make sense to keep `getStmt`? It could still return null but some callers might find it useful. 

https://github.com/llvm/llvm-project/pull/128251