Second attempt to fix buildbot failure caused by r332363

http://lab.llvm.org:8011/builders/clang-x86_64-linux-abi-test/builds/26501

llvm-svn: 332520
diff --git a/clang-tools-extra/clangd/CodeComplete.cpp b/clang-tools-extra/clangd/CodeComplete.cpp
index d00be58..1b1020a 100644
--- a/clang-tools-extra/clangd/CodeComplete.cpp
+++ b/clang-tools-extra/clangd/CodeComplete.cpp
@@ -1067,10 +1067,11 @@
   Options.IncludeMacros = false;
   Options.IncludeCodePatterns = false;
   Options.IncludeBriefComments = false;
+  std::vector<Inclusion> PreambleInclusions = {}; // Unused for signatureHelp
   semaCodeComplete(llvm::make_unique<SignatureHelpCollector>(Options, Result),
                    Options,
-                   {FileName, Command, Preamble, std::vector<Inclusion>(),
-                    Contents, Pos, std::move(VFS), std::move(PCHs)});
+                   {FileName, Command, Preamble, PreambleInclusions, Contents,
+                    Pos, std::move(VFS), std::move(PCHs)});
   return Result;
 }