[clang] [Clang] [NFC] Refactor more AST visitors (PR #116823)

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@@ -266,7 +265,7 @@ class RenameLocFinder : public RecursiveASTVisitor<RenameLocFinder> {
     return true;
   }
 
-  bool VisitDeclRefExpr(const DeclRefExpr *Expr) {
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cor3ntin wrote:

This makes sense but it is not amazing.
How hard do you think it would be to introduce something like `MutableDynamicRecursiveASTVisitor` and preserve constness where possible?

https://github.com/llvm/llvm-project/pull/116823