* Add SlotFill area to header
* Add activity panel fill
* Move activity panel to root client folder
* Move activity panel registration to its own folder
* Add navigation fill
* Add page title slotfill
* Slot fill the back button
* Move mobile banner to slot fill
* Fix navigation fill on embed pages
* Add changelog entry
* Allow order prop to header item fill
* Split header into before and after
* Fix header title gaps
* Fix nav and mobile app banner placement
* Fix display options import
* Only use last item for page header title fill
* Use function to pass fill props instead of bind
* Rename header slots
* Fix mobile banner dismissal check
* Fix up inbox panel rename
* Update task title in tests
* Fix up task status retrieval
* Migrate leaderboard tests to RTL.
* Remove test of default prop value.
* Migrate ReportSummary tests to RTL.
* Migrate ActivityCard tests to RTL.
* Migrate ActivityCardPlaceholder tests to RTL.
* Migrate remaining ProductType tests to RTL.
* Migrate Card tests to RTL.
* Update RTL and user event packages.
* Migrate Date tests to RTL.
* Migrate D3Legend tests to RTL.
* Migrate D3Base tests to RTL.
* Migrate Gravatar tests to RTL.
* Migrate ImageUpload tests to RTL.
* Migrate ProductImage tests to RTL.
* Migrate Rating tests to RTL.
* Migrate Search tests to RTL.
* Migrate Plugins tests to RTL.
* Migrate SelectControl tests to RTL.
* Migrate Timeline tests to RTL.
Remove tests that inspect DOM since there are snapshots.
* Migrate DismissModal tests to RTL.
* Migrate SetupNotice tests to RTL.
* Migrate WelcomeCard tests to RTL.
* Fix setup error reason retrieval in ShippingBanner.
* Migrate ShippingBanner tests to RTL.
* Migrate RecommendedExtensions tests to RTL.
* Migrate KnowledgeBase tests to RTL.
* Rename enzyme setup file, modify to setup RTL.
* No need to import jest-dom in test files.
* Remove enzyme dependency.
* Use snapshot for testing Leaderboard markup.
* Switch from "not to be empty" to "be in the document".
* No need to waitFor() recordEvent mock.
* Be specific about clicking the "hide" button.
* Use toBeVisible() instead of checking style property.