Revert "Continued fix for 351257. Reusing the feedback vector is too complex."

src/type-info.cc

Index: src/type-info.cc
diff --git a/src/type-info.cc b/src/type-info.cc
index 6282ef68f90acc6f6e3b74aab049704dc6f42699..35beb1808a6a8d4319237d3a31f66aa034b03466 100644
--- a/src/type-info.cc
+++ b/src/type-info.cc
@@ -43,12 +43,16 @@ namespace internal {
 
 
 TypeFeedbackOracle::TypeFeedbackOracle(Handle<Code> code,
-                                       Handle<FixedArray> feedback_vector,
                                        Handle<Context> native_context,
                                        Zone* zone)
     : native_context_(native_context),
-      zone_(zone),
-      feedback_vector_(feedback_vector) {
+      zone_(zone) {
+  Object* raw_info = code->type_feedback_info();
+  if (raw_info->IsTypeFeedbackInfo()) {
+    feedback_vector_ = Handle<FixedArray>(TypeFeedbackInfo::cast(raw_info)->
+                                          feedback_vector());
+  }
+
   BuildDictionary(code);
   ASSERT(dictionary_->IsDictionary());
 }
@@ -128,9 +132,9 @@ bool TypeFeedbackOracle::CallNewIsMonomorphic(int slot) {
 
 byte TypeFeedbackOracle::ForInType(int feedback_vector_slot) {
   Handle<Object> value = GetInfo(feedback_vector_slot);
-  return value.is_identical_to(
-      TypeFeedbackInfo::UninitializedSentinel(isolate()))
-      ? ForInStatement::FAST_FOR_IN : ForInStatement::SLOW_FOR_IN;
+  return value->IsSmi() &&
+      Smi::cast(*value)->value() == TypeFeedbackInfo::kForInFastCaseMarker
+          ? ForInStatement::FAST_FOR_IN : ForInStatement::SLOW_FOR_IN;
 }