| Index: runtime/lib/string_patch.dart
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| diff --git a/runtime/lib/string_patch.dart b/runtime/lib/string_patch.dart
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| index 11db8fe066a8f4e74ede1e9d314ac6427f612edf..4547fa5b75b00ddfd318bb525d1247795c483cac 100644
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| --- a/runtime/lib/string_patch.dart
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| +++ b/runtime/lib/string_patch.dart
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| @@ -157,7 +157,7 @@ class _StringBase {
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|    static String _createStringFromIterable(Iterable<int> charCodes,
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|                                            int start, int end) {
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|      // Treat charCodes as Iterable.
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| -    if (charCodes is EfficientLength) {
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| +    if (charCodes is EfficientLengthIterable) {
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|        int length = charCodes.length;
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|        end = RangeError.checkValidRange(start, end, length);
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|        List charCodeList = new List.from(charCodes.take(end).skip(start),
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| 
 |