[clang] [clang] fix code synthesis context depth limit logic (PR #161103)

[Erich Keane via cfe-commits]

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@@ -616,29 +616,30 @@ Sema::InstantiatingTemplate::InstantiatingTemplate(
     Invalid = true;
     return;
   }
-  Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
+
+  CodeSynthesisContext Inst;
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erichkeane wrote:

This seems in desperate need of a constructor here :) 

https://github.com/llvm/llvm-project/pull/161103