pub/yaml_test and switch/case

[DartBot]

<img src="https://avatars.githubusercontent.com/u/384794?v=3" align="left" width="96" height="96"hspace="10"> Issue by scheglov
Originally opened as dart-lang/sdk#3539

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According to spec "11.8 Switch" - "It is a compile-time error if the expressions ek are not
compile-time constants, of type int or String, for all k 2 1::n.".

But fields in _Parser are not declared as "int" or "String".
So, this test will fail when we will enforce int/String in Analyser/Editor.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/46275?v=3" align="left" width="48" height="48"hspace="10"> Comment by munificent

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Set owner to @nex3.
Added Triaged label.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/384794?v=3" align="left" width="48" height="48"hspace="10"> Comment by scheglov

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Spec 0.11 allows constants of any type in switch/case.

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Added AssumedStale label.