Utils: Fix DomTree update for entry block

If SplitBlockPredecessors was used on a function entry block,
it wouldn't update the dominator tree.

llvm-svn: 323928
diff --git a/llvm/unittests/Transforms/Utils/Local.cpp b/llvm/unittests/Transforms/Utils/Local.cpp
index ab60122..9b305f73 100644
--- a/llvm/unittests/Transforms/Utils/Local.cpp
+++ b/llvm/unittests/Transforms/Utils/Local.cpp
@@ -100,7 +100,7 @@
   EXPECT_EQ(3U, BB->size());
 }
 
-std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
+static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
   SMDiagnostic Err;
   std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C);
   if (!Mod)