[es6] implement destructuring assignment

src/typing-asm.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/typing-asm.h"
 
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
@@ skipping 1193 matching lines @@
 #ifdef DEBUG
     PrintF("Computed type: ");
     computed_type_->Print();
     PrintF("Expected type: ");
     expected_type_->Print();
 #endif
     FAIL(expr, msg);
   }
   expected_type_ = save;
 }
+
+
+void AsmTyper::VisitRewritableExpression(RewritableExpression* expr) {
+  RECURSE(Visit(expr->expression()));
+}
+
+
 }  // namespace internal
 }  // namespace v8