Creates the scaffolding for an @angular/dev-infra-private package
which will not be published to npm but will be pushed to
https://github.com/angular/dev-infra-private-builds repo for each
commit to master.
The contents of this npm package will then be depended on via
package.json dependency for angular/angular angular/angular-cli and
angular/components.
PR Close#35862
This commit moves the build-related scripts
(`build-ivy-npm-packages.js`, `build-packages-dist.js` and
`package-builder.js`) to a dedicated directory to keep the `scripts/`
directory cleaner.
It also moves the logic for building the `zone.js` package to a separate
script, `zone-js-builder.js`, to make it re-usable. A subsequent commit
will use it to build the `zone.js` package when building the Ivy Angular
packages as well.
PR Close#35780
Joey Perrott
George Kalpakas