Revert "The current growth strategy for growable arrays allocates a backing array of size 2 at (emp…

runtime/lib/array_patch.dart

Index: runtime/lib/array_patch.dart
diff --git a/runtime/lib/array_patch.dart b/runtime/lib/array_patch.dart
index 463b0b77927ee13ad0f4ae8922124838f728105c..b1e5398127e89dac7626a4171c507d640f128828 100644
--- a/runtime/lib/array_patch.dart
+++ b/runtime/lib/array_patch.dart
@@ -47,6 +47,10 @@ class List<E> {
       list.add(e);
     }
     if (growable) return list;
+    if (list.length == 0) {
+      // Avoid getting an immutable list from makeListFixedLength.
+      return new _List<E>(0);
+    }
     return makeListFixedLength(list);
   }