Remove SlidingStateWindow and related code.

src/v8-counters.h

Index: src/v8-counters.h
diff --git a/src/v8-counters.h b/src/v8-counters.h
index ef43179ce8f5f2ab7166d892598a27b959996798..986e6dd6bb820a6a584e001fb832d586276d6619 100644
--- a/src/v8-counters.h
+++ b/src/v8-counters.h
@@ -373,16 +373,9 @@ class Counters {
     kSizeOfFIXED_ARRAY__##name,
     FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(COUNTER_ID)
 #undef COUNTER_ID
-#define COUNTER_ID(name) k_##name,
-    STATE_TAG_LIST(COUNTER_ID)
-#undef COUNTER_ID
     stats_counter_count
   };
 
-  StatsCounter* state_counters(StateTag state) {
-    return &state_counters_[state];
-  }
-
   void ResetHistograms();
 
  private:
@@ -425,15 +418,6 @@ class Counters {
   FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(SC)
 #undef SC
 
-  enum {
-#define COUNTER_ID(name) __##name,
-    STATE_TAG_LIST(COUNTER_ID)
-#undef COUNTER_ID
-    kSlidingStateWindowCounterCount
-  };
-
-  // Sliding state window counters.
-  StatsCounter state_counters_[kSlidingStateWindowCounterCount];
   friend class Isolate;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Counters);