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

src/arm64/lithium-arm64.h

Index: src/arm64/lithium-arm64.h
diff --git a/src/arm64/lithium-arm64.h b/src/arm64/lithium-arm64.h
index 1da3dd83666dde1219876c5b08a6904a02ad5c61..7e04dac35ce8a57bc1a534b34add73dce861d530 100644
--- a/src/arm64/lithium-arm64.h
+++ b/src/arm64/lithium-arm64.h
@@ -28,7 +28,6 @@ class LCodeGen;
   V(ArgumentsLength)                            \
   V(ArithmeticD)                                \
   V(ArithmeticT)                                \
-  V(ArrayShift)                                 \
   V(BitI)                                       \
   V(BitS)                                       \
   V(BoundsCheck)                                \
@@ -2888,21 +2887,6 @@ class LTransitionElementsKind V8_FINAL : public LTemplateInstruction<0, 2, 2> {
 };
 
 
-class LArrayShift V8_FINAL : public LTemplateInstruction<1, 2, 0> {
- public:
-  LArrayShift(LOperand* context, LOperand* object) {
-    inputs_[0] = context;
-    inputs_[1] = object;
-  }
-
-  LOperand* context() const { return inputs_[0]; }
-  LOperand* object() const { return inputs_[1]; }
-
-  DECLARE_CONCRETE_INSTRUCTION(ArrayShift, "array-shift")
-  DECLARE_HYDROGEN_ACCESSOR(ArrayShift)
-};
-
-
 class LTrapAllocationMemento V8_FINAL : public LTemplateInstruction<0, 1, 2> {
  public:
   LTrapAllocationMemento(LOperand* object, LOperand* temp1, LOperand* temp2) {