Fix #14318: Cherry-pick interrupted animation fix from master ea5c22ec12e6a548b1ec2d7b0dcd9f71bea8d5dd
Fix #14313: Optimize jQuery.merge for size. Close gh-1344.
Ref #14313: Further code and test improvements
No ticket: Hide the testing-support jQuery from tests
No ticket. Update packages, make the devDependencies list alphabetic.
Fix #13983. Switch to //# for sourcemap directives.