Update deprecated maps before generating optimized code.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 94fd487aa3eef6f6016bcb153e4c69ba2e608273..d094b87c938b197ed96e8e0bbf8380514922c838 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -7280,7 +7280,7 @@ MaybeObject* DescriptorArray::Merge(int verbatim,
   // Allocate a new descriptor array large enough to hold the required
   // descriptors, with minimally the exact same size as this descriptor array.
   MaybeObject* maybe_descriptors = DescriptorArray::Allocate(
-      new_size, Max(new_size, number_of_descriptors()) - new_size);
+      new_size, Max(new_size, other->number_of_descriptors()) - new_size);
   if (!maybe_descriptors->To(&result)) return maybe_descriptors;
   ASSERT(result->length() > length() ||
          result->NumberOfSlackDescriptors() > 0 ||