[symbolizer] Factor out conversion DILineInfo->JSON. NFC

[sepavloff]

Summary

Move the conversion of DILineInfo to JSON into a separate function, so
it can be used in other places too.

This is a prerequisite patch for implementation of symbol+offset lookup.

[jhenderson]

LGTM.

[sepavloff]

Thanks!

llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp

static json::Object toJSON(const Request &Request, StringRef ErrorMsg = "") {
   json::Object Json({{"ModuleName", Request.ModuleName.str()}});
   if (Request.Address)
     Json["Address"] = toHex(*Request.Address);
   if (!ErrorMsg.empty())
     Json["Error"] = json::Object({{"Message", ErrorMsg.str()}});
   return Json;
 }
 
-void JSONPrinter::print(const Request &Request, const DILineInfo &Info) {
-  DIInliningInfo InliningInfo;
-  InliningInfo.addFrame(Info);
-  print(Request, InliningInfo);
-}
-
-void JSONPrinter::print(const Request &Request, const DIInliningInfo &Info) {
-  json::Array Array;
-  for (uint32_t I = 0, N = Info.getNumberOfFrames(); I < N; ++I) {
-    const DILineInfo &LineInfo = Info.getFrame(I);
-    json::Object Object(
-        {{"FunctionName", LineInfo.FunctionName != DILineInfo::BadString
-                              ? LineInfo.FunctionName
-                              : ""},
-         {"StartFileName", LineInfo.StartFileName != DILineInfo::BadString
-                               ? LineInfo.StartFileName
-                               : ""},
-         {"StartLine", LineInfo.StartLine},
-         {"StartAddress",
-          LineInfo.StartAddress ? toHex(*LineInfo.StartAddress) : ""},
-         {"FileName",
-          LineInfo.FileName != DILineInfo::BadString ? LineInfo.FileName : ""},
-         {"Line", LineInfo.Line},
-         {"Column", LineInfo.Column},
-         {"Discriminator", LineInfo.Discriminator}});
+static json::Object toJSON(const DILineInfo &LineInfo) {
+  return json::Object(
+}
+
+void JSONPrinter::print(const Request &Request, const DILineInfo &Info) {
+  DIInliningInfo InliningInfo;
+  InliningInfo.addFrame(Info);
+  print(Request, InliningInfo);
+}
+
+void JSONPrinter::print(const Request &Request, const DIInliningInfo &Info) {
+  json::Array Array;
+  for (uint32_t I = 0, N = Info.getNumberOfFrames(); I < N; ++I) {
+    const DILineInfo &LineInfo = Info.getFrame(I);
+    json::Object Object = toJSON(LineInfo);
     SourceCode SourceCode(LineInfo.FileName, LineInfo.Line,
                           Config.SourceContextLines, LineInfo.Source);
     std::string FormattedSource;
     raw_string_ostream Stream(FormattedSource);
     SourceCode.format(Stream);
     if (!FormattedSource.empty())
       Object["Source"] = std::move(FormattedSource);
     Array.push_back(std::move(Object));