when creating custom warning diagnostics, do not attempt to map
them with -Werror.  Custom diags cannot be mapped, and this makes
-Werror cause a determinstic crash for the checker and other
clients of the custom diagnostics machinery.  rdar://6816191


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70639 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index d5d8da1..3b3d61b 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -162,11 +162,6 @@
         unsigned ID = DiagInfo.size()+DIAG_UPPER_LIMIT;
         DiagIDs.insert(std::make_pair(D, ID));
         DiagInfo.push_back(D);
-
-        // If this is a warning, and all warnings are supposed to map to errors,
-        // insert the mapping now.
-        if (L == Diagnostic::Warning && Diags.getWarningsAsErrors())
-          Diags.setDiagnosticMapping((diag::kind)ID, diag::MAP_ERROR);
         return ID;
       }
     };