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

src/arm/macro-assembler-arm.cc

Index: src/arm/macro-assembler-arm.cc
diff --git a/src/arm/macro-assembler-arm.cc b/src/arm/macro-assembler-arm.cc
index 81a2d37643d2b018ae16d817559e0e9a0063214d..fb379e2b8e1ac2251c1a2d5b051a395619e3dc56 100644
--- a/src/arm/macro-assembler-arm.cc
+++ b/src/arm/macro-assembler-arm.cc
@@ -3089,6 +3089,16 @@ void MacroAssembler::JumpIfNotBothSequentialAsciiStrings(Register first,
 }
 
 
+void MacroAssembler::JumpIfNotUniqueName(Register reg,
+                                         Label* not_unique_name) {
+  STATIC_ASSERT(((SYMBOL_TYPE - 1) & kIsInternalizedMask) == kInternalizedTag);
+  cmp(reg, Operand(kInternalizedTag));
+  b(lt, not_unique_name);
+  cmp(reg, Operand(SYMBOL_TYPE));
+  b(gt, not_unique_name);
+}
+
+
 // Allocates a heap number or jumps to the need_gc label if the young space
 // is full and a scavenge is needed.
 void MacroAssembler::AllocateHeapNumber(Register result,