Expose -fobjc-nonfragile-abi2 as a top-level clang driver option.  Fixes <rdar://problem/8007063>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@104205 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 334a05d..602bd8f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1280,6 +1280,11 @@
           CmdArgs.push_back("-fobjc-dispatch-method=non-legacy");
       }
     }
+
+    // FIXME: -fobjc-nonfragile-abi2 is a transient option meant to expose
+    // features in testing.  It will eventually be removed.
+    if (Args.hasArg(options::OPT_fobjc_nonfragile_abi2))
+      CmdArgs.push_back("-fobjc-nonfragile-abi2");
   }
 
   if (!Args.hasFlag(options::OPT_fassume_sane_operator_new,