Change window to global in the most outer IIFE parameters. (cherry-picked from dc649a33e081c7beb083b04956731aa410eb6b3f)

In the most outer IIFE it’s not yet known if the global is window or not.
Using the window variable to denote the global was misleading in that case,
especially that the code didn’t make such assumption, requiring to provide
a Web-like window separately. Renaming window to global clears the confusion.
Fixes #14535: update Sizzle to 1.10.13
(cherry picked from commit c389c2e6ba698e95c683ad113d728e757a4da29a)
Add unit tests for .html( number ). Close gh-1447.
(cherry picked from commit ed291938c287d34fe1183e588e12372e540eb5e7)
Ajax: Use weak ETag header in tests

See http://en.wikipedia.org/wiki/HTTP_ETag#Strong_and_weak_validation

Close gh-1448
(cherry picked from commit d2aa969206aa1b7738b911cdaf29038f249b5066)
Fix #14579: attribute selectors with trailing spaces after an unquoted value
(cherry picked from commit ed20e7c645064822f4070a0c60195e4bcdaba683)