Fix bug with GVN on array loads.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
===================================================================
--- src/hydrogen-instructions.h	(revision 8225)
+++ src/hydrogen-instructions.h	(working copy)
@@ -595,6 +595,7 @@
   void SetOperandAt(int index, HValue* value);
 
   void DeleteAndReplaceWith(HValue* other);
+  void ReplaceAllUsesWith(HValue* other);
   bool HasNoUses() const { return use_list_ == NULL; }
   bool HasMultipleUses() const {
     return use_list_ != NULL && use_list_->tail() != NULL;
@@ -684,8 +685,6 @@
   // removed list node or NULL.
   HUseListNode* RemoveUse(HValue* value, int index);
 
-  void ReplaceAllUsesWith(HValue* other);
-
   void RegisterUse(int index, HValue* new_value);
 
   HBasicBlock* block_;
@@ -2403,6 +2402,7 @@
  public:
   HBoundsCheck(HValue* index, HValue* length)
       : HBinaryOperation(index, length) {
+    set_representation(Representation::Integer32());
     SetFlag(kUseGVN);
   }