Fix for potential issue related to replacing CheckMaps with values.

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index e0f6921b4d969d7aeffa6920baa465e4e9a6d96b..967bce473f759b23643290bb30c1161fdf171042 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -689,6 +689,9 @@ void HInstruction::PrintTo(StringStream* stream) {
   if (CheckFlag(HValue::kHasNoObservableSideEffects)) {
     stream->Add(" [noOSE]");
   }
+  if (CheckFlag(HValue::kIsDead)) {
+    stream->Add(" [dead]");
+  }
 }