The check for internalized strings relied on the fact that we had less

src/ia32/macro-assembler-ia32.h

Index: src/ia32/macro-assembler-ia32.h
diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h
index 7d780f0e11a51f39a94a45b6a5f97b94518b9d07..5cb8286bae20f40fd9ffd29f5fab788da074c122 100644
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -884,6 +884,15 @@ class MacroAssembler: public Assembler {
                                            Register scratch2,
                                            Label* on_not_flat_ascii_strings);
 
+  // Checks if the given register or operand is a unique name
+  void JumpIfNotUniqueName(Register reg, Label* not_unique_name,
+                           Label::Distance distance = Label::kFar) {
+    JumpIfNotUniqueName(Operand(reg), not_unique_name, distance);
+  }
+
+  void JumpIfNotUniqueName(Operand operand, Label* not_unique_name,
+                           Label::Distance distance = Label::kFar);
+
   static int SafepointRegisterStackIndex(Register reg) {
     return SafepointRegisterStackIndex(reg.code());
   }