Revert r160052, "Default to -std=c++11 on Windows.", for now.

Failing Tests (3):
    Clang :: Index/complete-cxx-inline-methods.cpp
    Clang :: Index/recursive-cxx-member-calls.cpp
    Clang :: SemaTemplate/inject-templated-friend-post.cpp

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160103 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 4e03603..66d792f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -2124,11 +2124,8 @@
     // eventually we want to do all the standard defaulting here instead of
     // splitting it between the driver and clang -cc1.
     if (!types::isCXX(InputType))
-      Args.AddAllArgsTranslated(CmdArgs, options::OPT_std_default_EQ,
-                                "-std=", /*Joined=*/true);
-    else if (getToolChain().getTriple().getOS() == llvm::Triple::Win32)
-      CmdArgs.push_back("-std=c++11");
-
+        Args.AddAllArgsTranslated(CmdArgs, options::OPT_std_default_EQ,
+                                  "-std=", /*Joined=*/true);
     Args.AddLastArg(CmdArgs, options::OPT_trigraphs);
   }