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

src/arm64/code-stubs-arm64.cc

Index: src/arm64/code-stubs-arm64.cc
diff --git a/src/arm64/code-stubs-arm64.cc b/src/arm64/code-stubs-arm64.cc
index bbcbdd3f14a7f68bf8ad19c5716187bb0ee63643..c8558957b173a390ec8deaffb115db85d8f184f3 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -356,17 +356,6 @@ void ElementsTransitionAndStoreStub::InitializeInterfaceDescriptor(
 }
 
 
-void ArrayShiftStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  // x0: receiver
-  static Register registers[] = { x0 };
-  descriptor->register_param_count_ = sizeof(registers) / sizeof(registers[0]);
-  descriptor->register_params_ = registers;
-  descriptor->deoptimization_handler_ =
-      Builtins::c_function_address(Builtins::c_ArrayShift);
-}
-
-
 void BinaryOpICStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
   // x1: left operand