| Index: utils/pub/system_cache.dart
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| diff --git a/utils/pub/system_cache.dart b/utils/pub/system_cache.dart
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| index 5b00dc301b6415bab3992b546f426860213de86b..fd2c6536122e1329e6e1170fb44aa71ff5c82b48 100644
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| --- a/utils/pub/system_cache.dart
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| +++ b/utils/pub/system_cache.dart
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| @@ -72,8 +72,8 @@ class SystemCache {
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|      var pending = _pendingInstalls[id];
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|      if (pending != null) return pending;
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|  
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| -    var future = id.source.installToSystemCache(id);
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| -    always(future, () => _pendingInstalls.remove(id));
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| +    var future = id.source.installToSystemCache(id)
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| +        .whenComplete(() => _pendingInstalls.remove(id));
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|      _pendingInstalls[id] = future;
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|      return future;
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|    }
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| 
 |