Fix HIsSmiAndBranch::KnownSuccessorBlock() by deleting it

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index c618fdfb544686061721f168ef1fed319f46419e..aa9c4cdb72cbacf9128879004e63e8b73351d720 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -4380,8 +4380,6 @@ class HIsSmiAndBranch V8_FINAL : public HUnaryControlInstruction {
     return Representation::Tagged();
   }
 
-  virtual bool KnownSuccessorBlock(HBasicBlock** block) V8_OVERRIDE;
-
  protected:
   virtual bool DataEquals(HValue* other) V8_OVERRIDE { return true; }
   virtual int RedefinedOperandIndex() { return 0; }