Support Go 1.16 `reflect` package.#996

Merged

nevkontakte merged 9 commits intogopherjs:go1.16-stdlibfrom

nevkontakte:go1.16-stdlib

Mar 16, 2021

Commits on Mar 16, 2021

Implement `runtime.FuncForPC()` for GopherJS.

nevkontakte
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flimzy
committed
Add a runtime type check on `return.MakeFunc()` return values.
nevkontakte
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Add missing `reflect.addReflectOff()` function implementation.

nevkontakte
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visualfc
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Provide a working implementation of `reflect.StructOf()` function.

nevkontakte
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visualfc
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Rename `mapitervalue` → `mapiterelem` in the `reflect` package.
nevkontakte
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Fix type string generation for channels and embedded struct fields.

nevkontakte
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visualfc
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Fix TestConvertNaNs test in the `reflect` package.

nevkontakte
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flimzy
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Enable source map support when running tests on CircleCI.
nevkontakte
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Update generated files with changes to `reflect` and `runtime`.
nevkontakte
committed