Eliminate the type distinction between BindInstr and DoInstr.

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/flow_graph_builder.h"
 #include "vm/il_printer.h"
 #include "vm/object_store.h"
 
@@ skipping 586 matching lines @@
     // Replace binary checks with unary ones since EmitNative expects it.
     ICData& unary_checks =
         ICData::Handle(ToUnaryClassChecks(*comp->ic_data()));
     comp->set_ic_data(&unary_checks);
   }
 
   TryFuseComparisonWithBranch(comp);
 }
 
 
-void FlowGraphOptimizer::VisitDo(DoInstr* instr) {
-  instr->computation()->Accept(this);
-}
-
-
 void FlowGraphOptimizer::VisitBind(BindInstr* instr) {
   instr->computation()->Accept(this);
 }
 
 
 
 FlowGraphAnalyzer::FlowGraphAnalyzer(
     const GrowableArray<BlockEntryInstr*>& blocks)
         :blocks_(blocks), is_leaf_(false) {}
 
@@ skipping 10 matching lines @@
           is_leaf_ = false;
           return;
         }
       }
       instr = instr->successor();
     }
   }
 }
 
 }  // namespace dart