[Interpreter] Add support for new.target

src/interpreter/bytecode-generator.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/interpreter/bytecode-generator.h"
 
 #include "src/compiler.h"
 #include "src/interpreter/control-flow-builders.h"
 #include "src/objects.h"
 #include "src/parser.h"
@@ skipping 2032 matching lines @@
 
   // Store the closure we were called with in the this_function_var.
   builder()->LoadAccumulatorWithRegister(Register::function_closure());
   VisitVariableAssignment(variable, FeedbackVectorSlot::Invalid());
 }
 
 
 void BytecodeGenerator::VisitNewTargetVariable(Variable* variable) {
   if (variable == nullptr) return;
 
-  // TODO(rmcilroy): Remove once we have tests which exercise this code path.
-  UNIMPLEMENTED();
-
   // Store the closure we were called with in the this_function_var.
   builder()->CallRuntime(Runtime::kGetOriginalConstructor, Register(), 0);
   VisitVariableAssignment(variable, FeedbackVectorSlot::Invalid());
 }
 
 
 void BytecodeGenerator::VisitFunctionClosureForContext() {
   AccumulatorResultScope accumulator_execution_result(this);
   Scope* closure_scope = execution_context()->scope()->ClosureScope();
   if (closure_scope->is_script_scope() ||
@@ skipping 97 matching lines @@
 }
 
 
 int BytecodeGenerator::feedback_index(FeedbackVectorSlot slot) const {
   return info()->feedback_vector()->GetIndex(slot);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8