Inline Array.shift() fast path instead of using a code stub.

src/arm64/lithium-arm64.cc

Index: src/arm64/lithium-arm64.cc
diff --git a/src/arm64/lithium-arm64.cc b/src/arm64/lithium-arm64.cc
index d365dcf96cf29faf0e33c1e80b3906b0abb4fd63..f38cec224c337d01b9b1cbc55191408a45396a2f 100644
--- a/src/arm64/lithium-arm64.cc
+++ b/src/arm64/lithium-arm64.cc
@@ -2523,14 +2523,6 @@ LInstruction* LChunkBuilder::DoTransitionElementsKind(
 }
 
 
-LInstruction* LChunkBuilder::DoArrayShift(HArrayShift* instr) {
-  LOperand* object = UseFixed(instr->object(), x0);
-  LOperand* context = UseFixed(instr->context(), cp);
-  LArrayShift* result = new(zone()) LArrayShift(context, object);
-  return MarkAsCall(DefineFixed(result, x0), instr, CANNOT_DEOPTIMIZE_EAGERLY);
-}
-
-
 LInstruction* LChunkBuilder::DoTrapAllocationMemento(
     HTrapAllocationMemento* instr) {
   LOperand* object = UseRegister(instr->object());