Correct error reporting bit for parallel PNaCl bitcode parses.

lib/Bitcode/NaCl/Reader/NaClBitstreamReader.cpp

Index: lib/Bitcode/NaCl/Reader/NaClBitstreamReader.cpp
diff --git a/lib/Bitcode/NaCl/Reader/NaClBitstreamReader.cpp b/lib/Bitcode/NaCl/Reader/NaClBitstreamReader.cpp
index 630ecdaa3316e619734fb965c3920ff8fa311b82..8aab59d43ca1ba8f04b753265a7c8e958b722301 100644
--- a/lib/Bitcode/NaCl/Reader/NaClBitstreamReader.cpp
+++ b/lib/Bitcode/NaCl/Reader/NaClBitstreamReader.cpp
@@ -49,7 +49,8 @@ Fatal(const std::string &ErrorMessage) const {
   // the error occurred.
   std::string Buffer;
   raw_string_ostream StrBuf(Buffer);
-  naclbitc::ErrorAt(StrBuf, naclbitc::Fatal, getCurrentBitNo()) << ErrorMessage;
+  naclbitc::ErrorAt(StrBuf, naclbitc::Fatal,
+                    Cursor.getErrorBitNo(getCurrentBitNo())) << ErrorMessage;
   report_fatal_error(StrBuf.str());
 }