| Index: src/runtime/runtime-strings.cc
 | 
| diff --git a/src/runtime/runtime-strings.cc b/src/runtime/runtime-strings.cc
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| index a126e8cd6379a92f766636036da5e9dcfc2903d6..31d9f1fc6ede906c8cae1d4be3036db6a7336107 100644
 | 
| --- a/src/runtime/runtime-strings.cc
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| +++ b/src/runtime/runtime-strings.cc
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| @@ -263,9 +263,6 @@ RUNTIME_FUNCTION(Runtime_StringBuilderConcat) {
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|    if (length == -1) {
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|      return isolate->Throw(isolate->heap()->illegal_argument_string());
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|    }
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| -  if (length == 0) {
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| -    return isolate->heap()->empty_string();
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| -  }
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|  
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|    if (one_byte) {
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|      Handle<SeqOneByteString> answer;
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| 
 |