[FeedbackVector] Infrastructure for literal arrays in the vector.

test/cctest/test-feedback-vector.cc

Index: test/cctest/test-feedback-vector.cc
diff --git a/test/cctest/test-feedback-vector.cc b/test/cctest/test-feedback-vector.cc
index 1f9ddc6f55ea22e23f2c2c3ccd13303e8d379edd..8ff4997c0115a87aaf3291c5e5dd2fa42c0c5bb8 100644
--- a/test/cctest/test-feedback-vector.cc
+++ b/test/cctest/test-feedback-vector.cc
@@ -95,6 +95,20 @@ TEST(VectorStructure) {
                          FeedbackVectorSlotKind::CALL_IC),
              vector->length());
   }
+
+  {
+    FeedbackVectorSpec spec(&zone);
+    spec.AddGeneralSlot();
+    spec.AddCreateClosureSlot(5);
+    spec.AddGeneralSlot();
+    vector = NewTypeFeedbackVector(isolate, &spec);
+    FeedbackVectorHelper helper(vector);
+    CHECK_EQ(1, TypeFeedbackMetadata::GetSlotSize(
+                    FeedbackVectorSlotKind::CREATE_CLOSURE));
+    FeedbackVectorSlot slot = helper.slot(1);
+    FixedArray* array = FixedArray::cast(vector->Get(slot));
+    CHECK_EQ(array, *factory->empty_literals_array());
+  }
 }