Allow the default values to be specified in the methods of interfaces

[DartBot]

This issue was originally filed by @tomyeh

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It will be better if we can specify the default values for the parameters of interface methods.
For example,

interface Foo {
  Foo([int v=0]);
  void f([int v=0]);
}

[DartBot]

This comment was originally written by [email protected]

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This is a duplicate of issue #2207, which is already fixed in the forthcoming version of the specification. I think this should be classified as a duplicate.

[DartBot]

This comment was originally written by @tomyeh

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My bad. It is a duplicate. Please close it.

[anders-sandholm]

Thanks (again), Ladislav :-)

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Added Duplicate label.
Marked as being merged into #2207.