DescriptorArray::IsProperty-related cleanup.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index d3d2d8fdeaa72ecd0f12655e9615f9325f76111f..eedd9ee193201a33a34992225d64615f8f11ea82 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -3773,12 +3773,14 @@ MaybeObject* JSObject::GetHiddenPropertiesDictionary(bool create_if_absent) {
     // code zero) it will always occupy the first entry if present.
     DescriptorArray* descriptors = this->map()->instance_descriptors();
     if ((descriptors->number_of_descriptors() > 0) &&
-        (descriptors->GetKey(0) == GetHeap()->hidden_symbol()) &&
-        descriptors->IsProperty(0)) {
-      ASSERT(descriptors->GetType(0) == FIELD);
-      Object* hidden_store =
-          this->FastPropertyAt(descriptors->GetFieldIndex(0));
-      return StringDictionary::cast(hidden_store);
+        (descriptors->GetKey(0) == GetHeap()->hidden_symbol())) {
+      if (descriptors->GetType(0) == FIELD) {
+        Object* hidden_store =
+            this->FastPropertyAt(descriptors->GetFieldIndex(0));
+        return StringDictionary::cast(hidden_store);
+      } else {
+        ASSERT(descriptors->GetType(0) == MAP_TRANSITION);
+      }
     }
   } else {
     PropertyAttributes attributes;
@@ -3819,11 +3821,13 @@ MaybeObject* JSObject::SetHiddenPropertiesDictionary(
     // code zero) it will always occupy the first entry if present.
     DescriptorArray* descriptors = this->map()->instance_descriptors();
     if ((descriptors->number_of_descriptors() > 0) &&
-        (descriptors->GetKey(0) == GetHeap()->hidden_symbol()) &&
-        descriptors->IsProperty(0)) {
-      ASSERT(descriptors->GetType(0) == FIELD);
-      this->FastPropertyAtPut(descriptors->GetFieldIndex(0), dictionary);
-      return this;
+        (descriptors->GetKey(0) == GetHeap()->hidden_symbol())) {
+      if (descriptors->GetType(0) == FIELD) {
+        this->FastPropertyAtPut(descriptors->GetFieldIndex(0), dictionary);
+        return this;
+      } else {
+        ASSERT(descriptors->GetType(0) == MAP_TRANSITION);
+      }
     }
   }
   MaybeObject* store_result =
@@ -5832,14 +5836,14 @@ MaybeObject* DescriptorArray::RemoveTransitions() {
   // not be allocated.
 
   // Compute the size of the map transition entries to be removed.
-  int num_removed = 0;
+  int new_number_of_descriptors = 0;
   for (int i = 0; i < number_of_descriptors(); i++) {
-    if (!IsProperty(i)) num_removed++;
+    if (IsProperty(i)) new_number_of_descriptors++;
   }
 
   // Allocate the new descriptor array.
   DescriptorArray* new_descriptors;
-  { MaybeObject* maybe_result = Allocate(number_of_descriptors() - num_removed);
+  { MaybeObject* maybe_result = Allocate(new_number_of_descriptors);
     if (!maybe_result->To<DescriptorArray>(&new_descriptors)) {
       return maybe_result;
     }