Revert "Windows: Add support for unicode command lines"

This is causing MinGW bots to fail.
This reverts commit r192069.

llvm-svn: 192070
diff --git a/llvm/lib/Support/Windows/DynamicLibrary.inc b/llvm/lib/Support/Windows/DynamicLibrary.inc
index 5a7b219..2edaf74 100644
--- a/llvm/lib/Support/Windows/DynamicLibrary.inc
+++ b/llvm/lib/Support/Windows/DynamicLibrary.inc
@@ -83,15 +83,8 @@
     // This is mostly to ensure that the return value still shows up as "valid".
     return DynamicLibrary(&OpenedHandles);
   }
-
-  SmallVector<wchar_t, MAX_PATH> filenameUnicode;
-  if (error_code ec = windows::UTF8ToUTF16(filename, filenameUnicode)) {
-    SetLastError(ec.value());
-    MakeErrMsg(errMsg, std::string(filename) + ": Can't convert to UTF-16: ");
-    return DynamicLibrary();
-  }
   
-  HMODULE a_handle = LoadLibraryW(filenameUnicode.data());
+  HMODULE a_handle = LoadLibrary(filename);
 
   if (a_handle == 0) {
     MakeErrMsg(errMsg, std::string(filename) + ": Can't open : ");