- It is intentionally invalid semver as pre versions should never be released
- UI and Mobile already do this

Fix #14584

Fixes #14016.

Ref #14016

And remove unused "which" package

Closes gh-1458

grunt-contrib-jshint 0.7.1 allows the jshintrc option to be set to true to have
it read the appropriate config file based on the file being checked. The only
place where we can’t use it is the check for dist/jquery.js that has the onevar
option removed.

Fixes #14504

.gitignore/.npmignore treat all its paths as relative to *every*
directory in the repository. In most cases that’s not what’s desired.

Chrome 31 doesn't fire Ajax requests in beforeunload event handler.
There is no way for us to workaround it and it's been fixed in Chrome 32
so let's just blacklist Chrome 31 as long as it's in TestSwarm.
See https://code.google.com/p/chromium/issues/detail?id=321241

Close gh-1421

This reverts commit 498e0e6c.

We can't use the ActiveX XHR because it doesn't support events.

Tracked bower dependencies are located at "src/sizzle" and "test/libs".
The source-destination mapping is in the Gruntfile.

When updating a bower dependency, update the version in bower.json, run
`grunt bower`, and then commit the result. When adding a dependency,
update the bowercopy task accordingly.

Fixes #14615.
Closes gh-1452.

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

Close gh-1448

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.

(cherry picked from commit 27b22f4e)
(cherry picked from commit 8dc0f2ea)
(cherry picked from commit 936126f1)

We can't feature detect ActiveX in IE11, but we can just call
it and catch whatever error occurs, then try normal XHR.

This also reduces memory leaks if the element is removed without cleaning
events (e.g with native DOM operations).

Not pickable into the 1.x branch because oldIE still needs this.