[clang] [NFCI][analyzer] Regularize NodeBuilder classes (PR #180960)

[Donát Nagy via cfe-commits]

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@@ -399,55 +399,56 @@ class BranchNodeBuilder: public NodeBuilder {
                              ExplodedNode *Pred);
 };
 
-class IndirectGotoNodeBuilder {
-  const CoreEngine &Eng;
-  const CFGBlock *Src;
+class IndirectGotoNodeBuilder : public NodeBuilder {
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NagyDonat wrote:

Good points, thanks for mentioning them.

I was aware of `anchor` methods, but I didn't think deeply about their purpose and vaguely felt that the presence of some out-of-line methods makes them unnecessary. (Those were not virtual methods.)

https://github.com/llvm/llvm-project/pull/180960