Add a wrapper for open.

This centralizes the handling of O_BINARY and opens the way for hiding more
differences (like how open behaves with directories).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186447 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Timer.cpp b/lib/Support/Timer.cpp
index 896d869..100b21e 100644
--- a/lib/Support/Timer.cpp
+++ b/lib/Support/Timer.cpp
@@ -66,8 +66,8 @@
   // compensate for this, the test-suite Makefiles have code to delete the
   // info output file before running commands which write to it.
   std::string Error;
-  raw_ostream *Result = new raw_fd_ostream(OutputFilename.c_str(),
-                                           Error, raw_fd_ostream::F_Append);
+  raw_ostream *Result =
+      new raw_fd_ostream(OutputFilename.c_str(), Error, sys::fs::F_Append);
   if (Error.empty())
     return Result;