#9808 - Dart double cast

[MichaelMarner]

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Description of the PR

This PR resolves #9808 by explicitly casting double properties from JSON payloads before assignment. This works around dart's JsonCodec parsing numbers that look like ints to int, which cannot then be assigned directly to a double.

This PR takes advantage of the fact all Dart's number types have a toDouble method. As long as the JSON payload contains a number, calling toDouble is safe.

@ircecho

[MichaelMarner]

Have added a check for null before parsing toDouble to prevent exception being thrown in the case where the data is not present in the json payload.

[MichaelMarner]

Hey just wondering the likelihood of this PR being merged, or if there's anything further I can do to get it merged?

[skordesign]

@MichaelMarner I saw The Travis CI build failed, have you try to solve it?

[MichaelMarner]

@skordesign sync'd with master, which made Travis pass. Thanks

[skordesign]

Any update? Still open?

[sm2017]

Why no one accept the PR?