[clang] [clang-transformer] Allow stencils to read from system headers. (PR #66480)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -230,7 +230,7 @@ class SelectorStencil : public StencilInterface {
       // message. If it's valid, then something else is the cause and we just
       // return the generic failure message.
       if (auto Err =
-              tooling::validateEditRange(*RawRange, *Match.SourceManager))
+              tooling::validateRange(*RawRange, *Match.SourceManager, true))
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ymand wrote:

Please use `/*AllowSystemHeaders=*/` before `true`, here and below.

https://github.com/llvm/llvm-project/pull/66480