Update for llvm api change.

llvm-svn: 216397
diff --git a/clang/lib/Frontend/ModuleDependencyCollector.cpp b/clang/lib/Frontend/ModuleDependencyCollector.cpp
index 485ca0a..882bf8ee 100644
--- a/clang/lib/Frontend/ModuleDependencyCollector.cpp
+++ b/clang/lib/Frontend/ModuleDependencyCollector.cpp
@@ -48,9 +48,9 @@
   SmallString<256> Dest = getDest();
   llvm::sys::path::append(Dest, "vfs.yaml");
 
-  std::string ErrorInfo;
-  llvm::raw_fd_ostream OS(Dest.c_str(), ErrorInfo, llvm::sys::fs::F_Text);
-  if (!ErrorInfo.empty()) {
+  std::error_code EC;
+  llvm::raw_fd_ostream OS(Dest, EC, llvm::sys::fs::F_Text);
+  if (EC) {
     setHasErrors();
     return;
   }