Fixed template in HeapSnapshotClassReferences implementation

runtime/observatory/lib/src/heap_snapshot/heap_snapshot.dart

Index: runtime/observatory/lib/src/heap_snapshot/heap_snapshot.dart
diff --git a/runtime/observatory/lib/src/heap_snapshot/heap_snapshot.dart b/runtime/observatory/lib/src/heap_snapshot/heap_snapshot.dart
index 71f41e4f948d29e813ee2938da7d779abdcead18..d20fc0a182285d2c0fb8646dbba0efbe5db4c572 100644
--- a/runtime/observatory/lib/src/heap_snapshot/heap_snapshot.dart
+++ b/runtime/observatory/lib/src/heap_snapshot/heap_snapshot.dart
@@ -177,7 +177,9 @@ class MergedVertex implements M.HeapSnapshotClassReferences {
     if (_inbounds != null) {
       return _inbounds;
     } else {
-      return _inbounds = new List.unmodifiable(
+      // It is important to keep the template.
+      // https://github.com/dart-lang/sdk/issues/27144
+      return _inbounds = new List<HeapSnapshotClassInbound>.unmodifiable(
         incomingEdges.map((edge) {
           return new HeapSnapshotClassInbound(this, edge);
         })
@@ -190,7 +192,9 @@ class MergedVertex implements M.HeapSnapshotClassReferences {
     if (_outbounds != null) {
       return _outbounds;
     } else {
-      return _outbounds = new List.unmodifiable(
+      // It is important to keep the template.
+      // https://github.com/dart-lang/sdk/issues/27144
+      return _outbounds = new List<HeapSnapshotClassOutbound>.unmodifiable(
         outgoingEdges.values.map((edge) {
           return new HeapSnapshotClassInbound(this, edge);

[Cutch, 2016/08/24 23:00:46]

Should this be HeapSNapshotClassOutbound?

[cbernaschina, 2016/08/24 23:04:36]

see https://codereview.chromium.org/2277073002/

         })