[lldb] Move Module::FindTypes scoped timer to SymbolFileDWARFDebugMap

[kastiglione]

Summary

When debugging via debug map, Module::FindTypes is called for very frequently
due to lookups happening over the possibly large set of object files.

Where a scoped timer is useful, it can placed in SymbolFile subclasses. This
change adds a scoped timer to SymbolFileDWARFDebugMap::FindTypes.

Also, deletes some nearby long commented out code.

[JDevlieghere]

LGTM

[kastiglione]

Merged in rG3ca91adef8e885d89658a540860d3cee8746b1d9

lldb/source/Core/Module.cpp

     llvm::ArrayRef<CompilerContext> pattern, LanguageSet languages,
     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
     TypeMap &types) {
-  LLDB_SCOPED_TIMER();
+  // If a scoped timer is needed, place it in a SymbolFile::FindTypes override.
+  // A timer here is too high volume for some cases, for example when calling
+  // FindTypes on each object file.
   if (SymbolFile *symbols = GetSymbolFile())
     symbols->FindTypes(pattern, languages, searched_symbol_files, types);
 }

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp

     llvm::ArrayRef<CompilerContext> context, LanguageSet languages,
     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
     TypeMap &types) {
+  LLDB_SCOPED_TIMER();
   ForEachSymbolFile([&](SymbolFileDWARF *oso_dwarf) -> bool {
     oso_dwarf->FindTypes(context, languages, searched_symbol_files, types);
     return false;
   });
 }
 
-//
-// uint32_t
-// SymbolFileDWARFDebugMap::FindTypes (const SymbolContext& sc, const
-// RegularExpression& regex, bool append, uint32_t max_matches, Type::Encoding
-// encoding, lldb::user_id_t udt_uid, TypeList& types)
-//{
-//  SymbolFileDWARF *oso_dwarf = GetSymbolFile (sc);
-//  if (oso_dwarf)
-//      return oso_dwarf->FindTypes (sc, regex, append, max_matches, encoding,
-//      udt_uid, types);
-//  return 0;
-//}
-
 CompilerDeclContext SymbolFileDWARFDebugMap::FindNamespace(
     lldb_private::ConstString name,
     const CompilerDeclContext &parent_decl_ctx) {