[clang] [BoundsSafety] Support late parsing for `counted_by` in type positions (PR #166491)

[Aaron Ballman via cfe-commits]

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@@ -1161,10 +1161,13 @@ class Parser : public CodeCompletionHandler {
     IdentifierInfo *MacroII = nullptr;
     SourceLocation AttrNameLoc;
     SmallVector<Decl *, 2> Decls;
+    unsigned NestedTypeLevel;
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AaronBallman wrote:

Yeah, this feels like it's leaking an implementation detail for bounds safety into something more generally used for late parsed attributes.

https://github.com/llvm/llvm-project/pull/166491