[llvm] [clang][modules] Move `SLocEntry` search into `ASTReader` (PR #66966)

[Jan Svoboda via llvm-commits]

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@@ -50,6 +50,7 @@ int y = a2<int>;
 // CHECK: In module 'a':
 // CHECK-NEXT: a.h:1:45: error:
 
+int z = b<int>;
 // MISSING-B: could not find file '{{.*}}b.h'
 // MISSING-B-NOT: please delete the module cache
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jansvoboda11 wrote:

I'm not sure. To me, this seems like an implementation detail we shouldn't test for.

https://github.com/llvm/llvm-project/pull/66966