Merge branch '7.2.1'

Merge branch '7.2.1'

Merge branch '7.2.1'

Merge pull request wikimedia#4493 from wikimedia/T280700

Table of Contents iPad crash fix

Merge pull request wikimedia#4489 from wikimedia/pre-release-testing-…

…fixes

Fix issues when testing article load times

Merge pull request wikimedia#4489 from wikimedia/pre-release-testing-…

…fixes

Fix issues when testing article load times

Merge pull request wikimedia#4489 from wikimedia/pre-release-testing-…

…fixes

Fix issues when testing article load times

Merge pull request wikimedia#4491 from wikimedia/T331902

Clear out featured article widget cache if article data changed

Merge pull request wikimedia#4487 from wikimedia/crash-fixes-1

Crash fixes

Merge pull request wikimedia#4487 from wikimedia/crash-fixes-1

Crash fixes