Update ember-source to the latest version 🚀

[greenkeeper]

Version 2.12.0 of ember-source just got published.

Dependency	ember-source
Current Version	2.11.3
Type	devDependency

The version 2.12.0 is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of ember-source.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

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Commits

The new version differs by 280 commits (ahead by 280, behind by 90).

• 1841cd8 Release v2.12.0
• d91b748 More CHANGELOG typos [ci skip]
• 6568560 fix changelog typo [ci skip]
• b0d527b Typo [ci skip]
• 47cf31d Prepare CHANGELOG for 2.12.0 [ci skip]
• 2a1b600 Update factoryManagerCache initial value to not share factoryCache.
• 8fb1fb9 Adding test around factoryManager caching
• b542bc5 allocate iteration structures lazily (pt. 2)
• 09c1218 [Fixes #15001] Remove internal EmptyObject usage
• daefda7 [BUGFIX beta] [PERF] Cache FactoryManagers
• 25cf68a [BUGFIX beta] only defProp the deprecated container once per prototype
• 756c845 allocate iteration structures lazily
• bdb46eb [DOCS beta] factoryFor docs
• 51d039e Avoid a couple of redundant property loads.
• c104dcd Fix typo

There are 250 commits in total. See the full diff.

Not sure how things should work exactly?

There is a collection of frequently asked questions and of course you may always ask my humans.

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Your Greenkeeper Bot 🌴