[llvm] Create a CharSetConverter class with both iconv and icu support. (PR #138893)

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,232 @@
+//===- unittests/Support/CharSetTest.cpp - Charset conversion tests -------===//
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s-barannikov wrote:

FWIW Per latest coding standard, this line can be the same as line 7.
(the file name should be updated)

https://github.com/llvm/llvm-project/pull/138893