[clang-tools-extra] [clang-doc] add ftime profiling (PR #97644)

[via cfe-commits]

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@@ -30,6 +35,7 @@ template <typename T> bool MapASTVisitor::mapDecl(const T *D) {
   if (D->getParentFunctionOrMethod())
     return true;
 
+  llvm::timeTraceProfilerBegin("emit info phase", "emit info");
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PeterChou1 wrote:

emit info was originally meant to mean the code path where the mapper serialized the ASTNode into clang-docs Info record

https://github.com/llvm/llvm-project/pull/97644