[interpreter, debugger] implement debugger statement.

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

 // Copyright 2015 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 27 matching lines @@
 
   builder.LoadLiteral(heap_num_0)
       .LoadLiteral(heap_num_1)
       .LoadLiteral(zero)
       .LoadLiteral(smi_0)
       .LoadLiteral(smi_1)
       .LoadAccumulatorWithRegister(reg_0)
       .LoadNamedProperty(reg_1, name, feedback_slot, LanguageMode::SLOPPY)
       .StoreAccumulatorInRegister(reg_2)
       .CallRuntime(Runtime::kLoadIC_Miss, reg_0, 1)
+      .Debugger()
       .Return();
 
   // Test iterator sees the expected output from the builder.
   BytecodeArrayIterator iterator(builder.ToBytecodeArray());
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kLdaConstant);
   CHECK(iterator.GetConstantForIndexOperand(0).is_identical_to(heap_num_0));
   CHECK(!iterator.done());
   iterator.Advance();
 
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kLdaConstant);
@@ skipping 33 matching lines @@
   iterator.Advance();
 
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kCallRuntime);
   CHECK_EQ(static_cast<Runtime::FunctionId>(iterator.GetIndexOperand(0)),
            Runtime::kLoadIC_Miss);
   CHECK_EQ(iterator.GetRegisterOperand(1).index(), reg_0.index());
   CHECK_EQ(iterator.GetCountOperand(2), 1);
   CHECK(!iterator.done());
   iterator.Advance();
 
+  CHECK_EQ(iterator.current_bytecode(), Bytecode::kDebugger);
+  CHECK(!iterator.done());
+  iterator.Advance();
+
   CHECK_EQ(iterator.current_bytecode(), Bytecode::kReturn);
   CHECK(!iterator.done());
   iterator.Advance();
   CHECK(iterator.done());
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8