Remove 'using std::error_code' from tools.

llvm-svn: 210876
diff --git a/llvm/tools/llvm-symbolizer/LLVMSymbolize.cpp b/llvm/tools/llvm-symbolizer/LLVMSymbolize.cpp
index 61c4e8a..c6bd4e7 100644
--- a/llvm/tools/llvm-symbolizer/LLVMSymbolize.cpp
+++ b/llvm/tools/llvm-symbolizer/LLVMSymbolize.cpp
@@ -26,10 +26,9 @@
 #include <stdlib.h>
 
 namespace llvm {
-using std::error_code;
 namespace symbolize {
 
-static bool error(error_code ec) {
+static bool error(std::error_code ec) {
   if (!ec)
     return false;
   errs() << "LLVMSymbolizer: error reading file: " << ec.message() << ".\n";
@@ -311,7 +310,7 @@
       const std::string &ResourcePath =
           getDarwinDWARFResourceForPath(Path);
       BinaryOrErr = createBinary(ResourcePath);
-      error_code EC = BinaryOrErr.getError();
+      std::error_code EC = BinaryOrErr.getError();
       if (EC != std::errc::no_such_file_or_directory && !error(EC)) {
         DbgBin = BinaryOrErr.get();
         ParsedBinariesAndObjects.push_back(std::unique_ptr<Binary>(DbgBin));