[Interpreter]: Add kRegList operand type for register list operands.

src/interpreter/bytecode-register-allocator.h

Index: src/interpreter/bytecode-register-allocator.h
diff --git a/src/interpreter/bytecode-register-allocator.h b/src/interpreter/bytecode-register-allocator.h
index ab57bf4e0079ac4158a6fc769cfdb4ac4291e454..e9de4661d30fad4299e845f372907efa6a260473 100644
--- a/src/interpreter/bytecode-register-allocator.h
+++ b/src/interpreter/bytecode-register-allocator.h
@@ -13,36 +13,6 @@ namespace v8 {
 namespace internal {
 namespace interpreter {
 
-class RegisterList {
- public:
-  RegisterList() : first_reg_index_(Register().index()), register_count_(0) {}
-  RegisterList(int first_reg_index, int register_count)
-      : first_reg_index_(first_reg_index), register_count_(register_count) {}
-
-  // Returns a new RegisterList which is a truncated version of this list, with
-  // |count| registers.
-  const RegisterList Truncate(int new_count) {
-    DCHECK_GE(new_count, 0);
-    DCHECK_LT(new_count, register_count_);
-    return RegisterList(first_reg_index_, new_count);
-  }
-
-  const Register operator[](size_t i) const {
-    DCHECK_LT(static_cast<int>(i), register_count_);
-    return Register(first_reg_index_ + static_cast<int>(i));
-  }
-
-  const Register first_register() const {
-    return (register_count() == 0) ? Register(0) : (*this)[0];
-  }
-
-  int register_count() const { return register_count_; }
-
- private:
-  int first_reg_index_;
-  int register_count_;
-};
-
 // A class that allows the allocation of contiguous temporary registers.
 class BytecodeRegisterAllocator final {
  public: