Removed useless Canonicalize implementations subsumed by dead code elimination.

Review URL: https://codereview.chromium.org/11362085

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12857 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/hydrogen-instructions.cc

@@ -859,16 +859,6 @@ void HLoadFieldByIndex::PrintDataTo(StringStream* stream) {
 }
 
 
-HValue* HConstant::Canonicalize() {
-  return HasNoUses() ? NULL : this;
-}
-
-
-HValue* HTypeof::Canonicalize() {
-  return HasNoUses() ? NULL : this;
-}
-
-
 HValue* HBitwise::Canonicalize() {
   if (!representation().IsInteger32()) return this;
   // If x is an int32, then x & -1 == x, x | 0 == x and x ^ 0 == x.

src/hydrogen-instructions.h

@@ -2610,7 +2610,6 @@ class HConstant: public HTemplateInstruction<0> {
   }
 
   virtual bool EmitAtUses() { return !representation().IsDouble(); }
-  virtual HValue* Canonicalize();
   virtual void PrintDataTo(StringStream* stream);
   virtual HType CalculateInferredType();
   bool IsInteger() { return handle()->IsSmi(); }
@@ -5034,7 +5033,6 @@ class HTypeof: public HTemplateInstruction<2> {
   HValue* context() { return OperandAt(0); }
   HValue* value() { return OperandAt(1); }
 
-  virtual HValue* Canonicalize();
   virtual void PrintDataTo(StringStream* stream);
 
   virtual Representation RequiredInputRepresentation(int index) {