Refactor toJS

[wangyiz4262]

PR checklist:

• Added unit tests
• Updated change log
• Verified that there is no significant performance drop (npm run perf)

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toJS will recursively convert an object containing Mobx observable value into a plain object

[coveralls]

Coverage increased (+0.1%) to 93.717% when pulling c52b25e on wangyiz4262:refactor-toJS into ff78f69 on mobxjs:master.

[mweststrate]

Hey @wangyiz4262, I can't approve the change as-is, as this would break with the current behavior, producing different results. I'm fine though if this behavior is applied when a special flag is applied, for example: { recurseEverything: true}. In that case make sure that there are unit tests covering both the flag enabled and disabled.

[wangyiz4262]

@mweststrate, thanks for the advice, will do!

[wangyiz4262]

Hi @mweststrate, I have added an optional flag as you suggested. Please check it out and merge if it is OK. Thanks!

[mweststrate]

Almost there 👍 left some questions / comments

[wangyiz4262]

Hi @mweststrate All comments have been addressed. And changes are also available for mobx4 in PR #1733

[mweststrate]

Thanks, merged! Will be part of next release

[mweststrate]

Released as 5.5.1. Sorry for the late release! Missed that a PR was pending for release

[stnwk]

Thanks! :)