Revert of Parse arrow functions at proper precedence level

src/pattern-rewriter.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/ast.h"
 #include "src/messages.h"
 #include "src/parser.h"
 
 namespace v8 {
 
@@ skipping 349 matching lines @@
       RelocInfo::kNoPosition);
   RecurseIntoSubpattern(node->target(), value);
 }
 
 
 void Parser::PatternRewriter::VisitSpread(Spread* node) {
   // TODO(dslomov): implement.
 }
 
 
-void Parser::PatternRewriter::VisitEmptyParentheses(EmptyParentheses* node) {
-  UNREACHABLE();
-}
-
-
 // =============== UNREACHABLE =============================
 
 void Parser::PatternRewriter::Visit(AstNode* node) { UNREACHABLE(); }
 
 #define NOT_A_PATTERN(Node)                                        \
   void Parser::PatternRewriter::Visit##Node(v8::internal::Node*) { \
     UNREACHABLE();                                                 \
   }
 
 NOT_A_PATTERN(BinaryOperation)
@@ skipping 34 matching lines @@
 NOT_A_PATTERN(TryFinallyStatement)
 NOT_A_PATTERN(UnaryOperation)
 NOT_A_PATTERN(VariableDeclaration)
 NOT_A_PATTERN(WhileStatement)
 NOT_A_PATTERN(WithStatement)
 NOT_A_PATTERN(Yield)
 
 #undef NOT_A_PATTERN
 }  // namespace internal
 }  // namespace v8