Temporary fix for pub crash by canonicalizing type only if the IsCreatedFromSnapshot bit is true (i…

runtime/vm/raw_object_snapshot.cc

Index: runtime/vm/raw_object_snapshot.cc
diff --git a/runtime/vm/raw_object_snapshot.cc b/runtime/vm/raw_object_snapshot.cc
index ccf9a76975d41a93beea3bdc18ade254133ca504..cc193fa18bb2f1a8e40c0ba7b0966ab9f76db8f3 100644
--- a/runtime/vm/raw_object_snapshot.cc
+++ b/runtime/vm/raw_object_snapshot.cc
@@ -210,7 +210,9 @@ RawType* Type::ReadFrom(SnapshotReader* reader,
   // Allocate type object.
   Type& type = Type::ZoneHandle(reader->zone(), NEW_OBJECT(Type));
   bool is_canonical = RawObject::IsCanonical(tags);
-  bool defer_canonicalization = is_canonical && (kind != Snapshot::kFull);
+  bool defer_canonicalization = is_canonical &&
+      ((kind == Snapshot::kScript && RawObject::IsCreatedFromSnapshot(tags)) ||
+       kind == Snapshot::kMessage);
   reader->AddBackRef(object_id, &type, kIsDeserialized, defer_canonicalization);
 
   // Set all non object fields.
@@ -451,7 +453,9 @@ RawTypeArguments* TypeArguments::ReadFrom(SnapshotReader* reader,
   TypeArguments& type_arguments = TypeArguments::ZoneHandle(
       reader->zone(), NEW_OBJECT_WITH_LEN_SPACE(TypeArguments, len, kind));
   bool is_canonical = RawObject::IsCanonical(tags);
-  bool defer_canonicalization = is_canonical && (kind != Snapshot::kFull);
+  bool defer_canonicalization = is_canonical &&
+      ((kind == Snapshot::kScript && RawObject::IsCreatedFromSnapshot(tags)) ||
+       kind == Snapshot::kMessage);
   reader->AddBackRef(object_id,
                      &type_arguments,
                      kIsDeserialized,