Attempt to fix buildbot after r353679 #2

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353683 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Support/Error.h b/include/llvm/Support/Error.h
index a7cf2d5..23a48ed 100644
--- a/include/llvm/Support/Error.h
+++ b/include/llvm/Support/Error.h
@@ -1195,7 +1195,7 @@
 private:
   FileError(const Twine &F, std::unique_ptr<ErrorInfoBase> E) {
     assert(E && "Cannot create FileError from Error success value.");
-    assert(!F.isEmpty() &&
+    assert(!F.isTriviallyEmpty() &&
            "The file name provided to FileError must not be empty.");
     FileName = F.str();
     Err = std::move(E);