Reduce the size of the generated sdk and the underlying dependencies (ms-rest-js and ms-rest-azure-js)

[azure]

Reduce the size of the generated sdk and the underlying dependencies (ms-rest-js and ms-rest-azure-js)

[XiaoningLiu]

For the callback/promise, aws-js SDK provides a runtime switch. We can have a look for reference.

https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/using-promises.html

[RikkiGibson]

It might actually make a measurable difference in bundle size to simplify some validations in generated code to smaller equivalents: e.g. foo === null || foo === undefined || typeof foo !== 'string' can be reduced to typeof foo !== 'string' (because typeof null === 'object' and typeof undefined === 'undefined')