Scheduler depends on common packages

[gaearon]

This adds common dependencies to scheduler.

• fbjs avoids duplication of invariant/warning between React and the scheduler package. This fixes the FB bundle too so that it doesn't ship a different invariant than the one we use normally.
• object-assign is not currently used but it will be if we add an Object.assign() call. In that case, if we don't specify it in dependencies, the polyfill will be inlined (which we don't want).

We can choose to drop these dependencies later by removing their use, but seems safer to add them now as we're not focused on the code size yet, and React already uses both of them anyway.

Test plan: yarn build scheduler --type=NODE,FB shouldn't include invariant or warning implementations in any bundles.

[pull-bot]

Details of bundled changes.

Comparing: ec60457...9f275d6

react-scheduler

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
react-scheduler.development.js	-25.6%	-25.3%	18.98 KB	14.11 KB	5.7 KB	4.25 KB	NODE_DEV
react-scheduler.production.min.js	-15.2%	-12.9%	3.25 KB	2.76 KB	1.55 KB	1.35 KB	NODE_PROD
ReactScheduler-dev.js	-26.3%	-26.1%	19.15 KB	14.11 KB	5.77 KB	4.26 KB	FB_WWW_DEV
ReactScheduler-prod.js	-10.0%	-11.4%	8.46 KB	7.62 KB	2.32 KB	2.06 KB	FB_WWW_PROD

Generated by 🚫 dangerJS

[flarnie]

[flarnie]

Agreed - will try to remove those dependencies later, but for now this makes sense.