[clang-tools-extra] [clang-doc] Add HTMLMustacheGenerator.cpp (PR #138060)

[Paul Kirth via cfe-commits]

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@@ -535,6 +535,8 @@ struct ClangDocContext {
   // JavaScript files that will be imported in all HTML files.
   std::vector<std::string> JsScripts;
   StringRef Base;
+  // Mustache Template files
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ilovepi wrote:

done. LMK if something is unclear.

https://github.com/llvm/llvm-project/pull/138060