| Index: lib/compiler/implementation/js_backend/backend.dart
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| diff --git a/lib/compiler/implementation/js_backend/backend.dart b/lib/compiler/implementation/js_backend/backend.dart
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| index a196406cf33fb5ebae21bece76cbd1a90cda1a8c..206da1d492afbc34cdf1aaa6b97c92bc3b2ccd55 100644
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| --- a/lib/compiler/implementation/js_backend/backend.dart
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| +++ b/lib/compiler/implementation/js_backend/backend.dart
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| @@ -422,9 +422,9 @@ class FieldTypesRegistry {
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|  
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|    void dump() {
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|      Set<Element> allFields = new Set<Element>();
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| -    fieldInitializerTypeMap.getKeys().forEach(allFields.add);
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| -    fieldConstructorTypeMap.getKeys().forEach(allFields.add);
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| -    fieldTypeMap.getKeys().forEach(allFields.add);
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| +    fieldInitializerTypeMap.keys.forEach(allFields.add);
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| +    fieldConstructorTypeMap.keys.forEach(allFields.add);
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| +    fieldTypeMap.keys.forEach(allFields.add);
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|      allFields.forEach((Element field) {
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|        print("Inferred $field has type ${optimisticFieldType(field)}");
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|      });
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| 
 |