Simplify redundant phi elimination and use during canonicalization too.

src/hydrogen-redundant-phi.h

 // Copyright 2013 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 24 matching lines @@
 
 
 // Replace all phis consisting of a single non-loop operand plus any number of
 // loop operands by that single non-loop operand.
 class HRedundantPhiEliminationPhase : public HPhase {
  public:
   explicit HRedundantPhiEliminationPhase(HGraph* graph)
       : HPhase("H_Redundant phi elimination", graph) { }
 
   void Run();
+  void ProcessBlock(HBasicBlock* block);
 
  private:
+  void ProcessPhis(const ZoneList<HPhi*>* phis);
+
   DISALLOW_COPY_AND_ASSIGN(HRedundantPhiEliminationPhase);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_REDUNDANT_PHI_H_