[clang] [clang] Fixed predefined expressions after lambda parameters (PR #211811)

[Corentin Jabot via cfe-commits]

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@@ -879,6 +879,8 @@ class LambdaScopeInfo final :
   /// is known.
   bool AfterParameterList = true;
 
+  bool BeforeCompoundStatement = false;
+
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cor3ntin wrote:

I think it would be easier to initialize that to `true` and only set it to false at the end of `ActOnStartOfLambdaDefinition`

https://github.com/llvm/llvm-project/pull/211811