[clang] [llvm] [Clang] Only define `wchar_size` module flag if non-standard (PR #184668)

[Joseph Huber via cfe-commits]

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@@ -1239,6 +1239,17 @@ class Triple {
     return isOSBinFormatXCOFF() || isWasm();
   }
 
+  /// Returns the default wchar_t size (in bytes) for this target triple.
+  unsigned getDefaultWCharSize() const {
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jhuber6 wrote:

Done

https://github.com/llvm/llvm-project/pull/184668