[924764] Redesign collection header and animations [r=crdlc]
Merge pull request #12805 from EverythingMe/924764-collection-design-changes

[924764] Redesign collection header and animations [r=crdlc]
Bug 926535 - Wait for the app to be fully repainted before starting the warm launch transition. r=alive
Merge pull request #12833 from vingtetun/warm.launch.repainted

Bug 926535 - Wait for the app to be fully repainted before starting the ...