[lit] Try errors="ignore" for decode introduced by r374665
[lit] Try errors="ignore" for decode introduced by r374665

Still trying to fix the same error as in r374666.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@374671 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm