Ref #14313: Optimize 1.x jQuery.merge for size.
(cherry picked from commits c75c9a8ebb5d2483daa68bec799e0d770083a811 f66d53c85643e703a8e37d9ca9375dd386a60cda)
No ticket: Hide the testing-support jQuery from tests
(cherry picked from commit 0c185209233f4c15e57c6a24e8f81b27dd26db59)

Conflicts:

	test/data/testrunner.js
WIP. Fix #10814. Fix #14084. Make support tests lazy and broken out to components.