[clangd] Respect Origin option in createStaticIndexingAction

[kadircet]

Summary

Currently createStaticIndexingAction always set Origin to Static, which
makes it hard to change it later on by different indexers(One needs to go over
each symbol making a new copy).

This patch changes that behavior to rather respect it if set by user.

clangd/index/IndexAction.h

 
 // Creates an action that indexes translation units and delivers the results
 // for SymbolsCallback (each slab corresponds to one TU).
 //
 // Only a subset of SymbolCollector::Options are respected:
 //   - include paths are always collected, and canonicalized appropriately
 //   - references are always counted
 //   - all references are collected (if RefsCallback is non-null)
-//   - the symbol origin is always Static
+//   - the symbol origin is set to Static if not specified by caller
 std::unique_ptr<FrontendAction> createStaticIndexingAction(
     SymbolCollector::Options Opts,
     std::function<void(SymbolSlab)> SymbolsCallback,
     std::function<void(RefSlab)> RefsCallback,
     std::function<void(IncludeGraph)> IncludeGraphCallback);
 
 } // namespace clangd
 } // namespace clang
 
 #endif

clangd/index/IndexAction.cpp

std::unique_ptr<FrontendAction> createStaticIndexingAction(
     std::function<void(SymbolSlab)> SymbolsCallback,
     std::function<void(RefSlab)> RefsCallback,
     std::function<void(IncludeGraph)> IncludeGraphCallback) {
   index::IndexingOptions IndexOpts;
   IndexOpts.SystemSymbolFilter =
       index::IndexingOptions::SystemSymbolFilterKind::All;
   Opts.CollectIncludePath = true;
   Opts.CountReferences = true;
+  if (Opts.Origin == SymbolOrigin::Unknown)
     Opts.Origin = SymbolOrigin::Static;
   Opts.StoreAllDocumentation = false;
   if (RefsCallback != nullptr) {
     Opts.RefFilter = RefKind::All;
     Opts.RefsInHeaders = true;
   }
   auto Includes = llvm::make_unique<CanonicalIncludes>();
   addSystemHeadersMapping(Includes.get());
   Opts.Includes = Includes.get();
   return llvm::make_unique<IndexAction>(
       std::make_shared<SymbolCollector>(std::move(Opts)), std::move(Includes),
       IndexOpts, SymbolsCallback, RefsCallback, IncludeGraphCallback);
 }
 
 } // namespace clangd
 } // namespace clang