Add per-library cache of exported names

runtime/vm/raw_object_snapshot.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/snapshot.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
@@ skipping 1164 matching lines @@
     }
     // Initialize cache of resolved names.
     const intptr_t kInitialNameCacheSize = 64;
     if (kind != Snapshot::kFull) {
       // The cache of resolved names in library scope is not serialized.
       library.InitResolvedNamesCache(kInitialNameCacheSize);
       library.Register();
     } else {
       library.InitResolvedNamesCache(kInitialNameCacheSize, reader);
     }
+    library.StorePointer(&library.raw_ptr()->exported_names_, Array::null());
     // Initialize cache of loaded scripts.
     library.StorePointer(&library.raw_ptr()->loaded_scripts_, Array::null());
   }
   return library.raw();
 }
 
 
 void RawLibrary::WriteTo(SnapshotWriter* writer,
                          intptr_t object_id,
                          Snapshot::Kind kind,
@@ skipping 2505 matching lines @@
     // We do not allow objects with native fields in an isolate message.
     writer->SetWriteException(Exceptions::kArgument,
                               "Illegal argument in isolate message"
                               " : (object is a UserTag)");
   } else {
     UNREACHABLE();
   }
 }
 
 }  // namespace dart