[Interpreter] Add support for calling runtime functions which return a pair.

test/unittests/interpreter/bytecode-array-builder-unittest.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/interpreter/bytecode-array-builder.h"
 #include "src/interpreter/bytecode-array-iterator.h"
 #include "test/unittests/test-utils.h"
 
@@ skipping 91 matching lines @@
 
   // Emit literal creation operations.
   builder.CreateRegExpLiteral(factory->NewStringFromStaticChars("a"), 0, 0)
       .CreateArrayLiteral(factory->NewFixedArray(1), 0, 0)
       .CreateObjectLiteral(factory->NewFixedArray(1), 0, 0);
 
   // Call operations.
   builder.Call(reg, reg, 0, 0)
       .Call(reg, reg, 0, 1024)
       .CallRuntime(Runtime::kIsArray, reg, 1)
+      .CallRuntimePair(Runtime::kLoadLookupSlot, reg, 1, reg)
       .CallJSRuntime(Context::SPREAD_ITERABLE_INDEX, reg, 1);
 
   // Emit binary operator invocations.
   builder.BinaryOperation(Token::Value::ADD, reg, Strength::WEAK)
       .BinaryOperation(Token::Value::SUB, reg, Strength::WEAK)
       .BinaryOperation(Token::Value::MUL, reg, Strength::WEAK)
       .BinaryOperation(Token::Value::DIV, reg, Strength::WEAK)
       .BinaryOperation(Token::Value::MOD, reg, Strength::WEAK);
 
   // Emit bitwise operator invocations
@@ skipping 559 matching lines @@
     iterator.Advance();
   }
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kReturn);
   iterator.Advance();
   CHECK(iterator.done());
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8