Remove unnecessary AST node for ++ and -- operations.

src/data-flow.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 472 matching lines @@
 }
 
 
 void AssignedVariablesAnalyzer::VisitUnaryOperation(UnaryOperation* expr) {
   ASSERT(av_.IsEmpty());
   MarkIfTrivial(expr->expression());
   Visit(expr->expression());
 }
 
 
-void AssignedVariablesAnalyzer::VisitIncrementOperation(
-    IncrementOperation* expr) {
-  UNREACHABLE();
-}
-
-
 void AssignedVariablesAnalyzer::VisitCountOperation(CountOperation* expr) {
   ASSERT(av_.IsEmpty());
   if (expr->is_prefix()) MarkIfTrivial(expr->expression());
   Visit(expr->expression());
 
   Variable* var = expr->expression()->AsVariableProxy()->AsVariable();
   if (var != NULL) RecordAssignedVar(var);
 }
 
 
@@ skipping 27 matching lines @@
   ASSERT(av_.IsEmpty());
 }
 
 
 void AssignedVariablesAnalyzer::VisitDeclaration(Declaration* decl) {
   UNREACHABLE();
 }
 
 
 } }  // namespace v8::internal