vector-based ICs did not update type feedback counts correctly.

src/utils.h

Index: src/utils.h
diff --git a/src/utils.h b/src/utils.h
index 5c58ff8e608d03df56ea9b1b082dffc726d95ec8..58bcb3ae746c4955e8b7957ccdc07527a1a57c26 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -951,21 +951,22 @@ class TypeFeedbackId {
 };
 
 
-class FeedbackVectorSlot {
+template <int dummy_parameter>
+class VectorSlot {
  public:
-  explicit FeedbackVectorSlot(int id) : id_(id) {}
+  explicit VectorSlot(int id) : id_(id) {}
   int ToInt() const { return id_; }
 
-  static FeedbackVectorSlot Invalid() {
-    return FeedbackVectorSlot(kInvalidSlot);
-  }
+  static VectorSlot Invalid() { return VectorSlot(kInvalidSlot); }
   bool IsInvalid() const { return id_ == kInvalidSlot; }
 
-  FeedbackVectorSlot next() const {
+  VectorSlot next() const {
     DCHECK(id_ != kInvalidSlot);
-    return FeedbackVectorSlot(id_ + 1);
+    return VectorSlot(id_ + 1);
   }
 
+  bool operator==(const VectorSlot& other) const { return id_ == other.id_; }
+
  private:
   static const int kInvalidSlot = -1;
 
@@ -973,6 +974,10 @@ class FeedbackVectorSlot {
 };
 
 
+typedef VectorSlot<0> FeedbackVectorSlot;
+typedef VectorSlot<1> FeedbackVectorICSlot;
+
+
 class BailoutId {
  public:
   explicit BailoutId(int id) : id_(id) { }