[clang] Disable -fdollars-in-identifiers by default (PR #135407)

[Owen Pan via cfe-commits]

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@@ -4036,6 +4036,7 @@ LangOptions getFormattingLangOpts(const FormatStyle &Style) {
   LangOpts.MicrosoftExt = 1;    // To get kw___try, kw___finally.
   LangOpts.DeclSpecKeyword = 1; // To get __declspec.
   LangOpts.C99 = 1; // To get kw_restrict for non-underscore-prefixed restrict.
+  LangOpts.DollarIdents = 1; // For $identifier$ testing.
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owenca wrote:

Should the comment be something like `To allow $ in identifiers.`?

https://github.com/llvm/llvm-project/pull/135407