[es6] implement default/optional parameters (WIP / comments)

src/full-codegen.h

 // Copyright 2012 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.
 
 #ifndef V8_FULL_CODEGEN_H_
 #define V8_FULL_CODEGEN_H_
 
 #include "src/v8.h"
 
 #include "src/allocation.h"
@@ skipping 576 matching lines @@
   void EmitResolvePossiblyDirectEval(int arg_count);
 
   // Platform-specific support for allocating a new closure based on
   // the given function info.
   void EmitNewClosure(Handle<SharedFunctionInfo> info, bool pretenure);
 
   // Re-usable portions of CallRuntime
   void EmitLoadJSRuntimeFunction(CallRuntime* expr);
   void EmitCallJSRuntimeFunction(CallRuntime* expr);
 
+  void EmitInitializeOptionalParameters(Scope* scope, FunctionLiteral* fn);
+
   // Platform-specific support for compiling assignments.
 
   // Left-hand side can only be a property, a global or a (parameter or local)
   // slot.
   enum LhsKind {
     VARIABLE,
     NAMED_PROPERTY,
     KEYED_PROPERTY,
     NAMED_SUPER_PROPERTY,
     KEYED_SUPER_PROPERTY
@@ skipping 491 matching lines @@
 
   Address start_;
   Address instruction_start_;
   uint32_t length_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_FULL_CODEGEN_H_