Dartboard doesn't show src location of runtime exception

[DartBot]

This issue was originally filed by duane.1...@gmail.com

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When code running within Dartboard code throws a fatal runtime exception, such as IndexOutOfRangeException, Dartboard does not show where in the Dart source the error occurred.

Example:

main() {
  var A = "abcde";
  print(A[12]);
}

throws the exception message
   IndexOutOfRangeException: 12
which shows the invalid index value, but not where in the Dart code it occurred, nor the name of the array or string object (if named), nor the upper bound on that object, nor the name of the functions active at the time of the fault.

Seen in http://try-dart-lang.appspot.com/s/2cMa on Oct 14.

[DartBot]

This comment was originally written by drfibonacci@google.com

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Removed Type-Defect label.
Added Type-Enhancement, Area-Dartboard, Triaged labels.

[DartBot]

This comment was originally written by antonm@google.com

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Added Fixed label.