[llvm] [clang-tools-extra] [clang] [clang] Ensure fixed point conversions work in C++ (PR #68344)

[via cfe-commits]

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@@ -156,7 +156,8 @@ ImplicitConversionRank clang::GetConversionRank(ImplicitConversionKind Kind) {
                      // it was omitted by the patch that added
                      // ICK_Zero_Queue_Conversion
     ICR_C_Conversion,
-    ICR_C_Conversion_Extension
+    ICR_C_Conversion_Extension,
+    ICR_C_Conversion_Extension,
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PiJoules wrote:

`ICR_C_Conversion_Extension` I picked pretty much because of the `Extension` bit. Functionally, using `ICR_Conversion` doesn't change anything since none of the other implicit conversion kinds that have a rank from `ICR_Conversion` to `ICR_C_Conversion_Extension` should be applicable for fixed point types. I think block check where we assign `ICK_Fixed_Point_Conversion` should make sure we don't add any other SCSs.

https://github.com/llvm/llvm-project/pull/68344