Dart2js: error: library not found dart:math

[DartBot]

This issue was originally filed by alexander.orlov@loxal.net

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type_trainer.dart:10:9: error: library not found dart:math

import('dart:math');

        ^^^^^^^^^^^
Error: Compilation failed.

Rev.: 8192

label: dart2js

[madsager]

cc @iposva-google.
Added Area-Library, Triaged labels.

[sethladd]

dart:math needs to make its way into the SDK, too.

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cc @dgrove.
Added Area-Build label.

[madsager]

Added Fixed label.

[anders-sandholm]

Removed Area-Library, Area-Build labels.
Added Area-Infrastructure label.