Update $.data to use a function instead of an object when attaching to JS objects in order to hide attached metadata from JSON.stringify. Remove event.js code that was doing this before specifically for events, which is now redundant. Fixes #8108. 1.5-stable

Adds jQuery collection to objects that will be used as global events context if provided in the ajax options.

Makes sure xhrs are actually aborted on unload in IE. Simplifies active xhrs caching in the process.

Fixes #8177. XHR transport now considers 304 Not Modified responses as 200 OK if no conditional request header was provided (as per the XMLHttpRequest specification).

Fixes abort in prefilter. No global event will be fired in that case even if the global option is set to true. Unit test added.

Don't use a local copy of jQuery.ajaxSettings.isLocal anymore but use the current value so that it is possible to set isLocal to true for protocols unknown to jQuery.

Stores jQuery.ajaxSettings.isLocal locally at load time so that any change to it won't affect the transport. Fixes the url parsing regexp to deal with empty domains. Adds informative text into test/localfile.html and handles Opera's failure. Revises the way xhr are created by doing all tests at load time and normalizes all the xhr creation functions so that none of them may throw an exception.

Fixes #7653. Changes regexp to detect local protocol so that it will accept any protocol finishing by -extension.

Fixes #8146. Custom fields in xhrFields are now set after the XMLHttpRequest object has been opened.

Fixes #8152 by applying the same special cases for protocol "chrome-extension:" as were for "file:" (needs tests). Re-organizes and fixes the handling of special cases for HTTP status code in the xhr transport. Also re-organizes the handling of document.location in ajax.js.

Fixes #8146 by introducing the xhrFields option with is a map of fieldName/fieldValue to set on the native xhr. Can be used to set withCredentials to true for cross-domain requests if needed.

Fixes #8138. Access to document.location is made only once at load time and if it fails (throwing an exception in IE when document.domain is already set), we use the href of an A element instead.

Fixes #8135. Makes sure any exception thrown by Firefox when trying to access an XMLHttpRequest property when a network error occured is caught and notified as an error. Added test/networkerror.html to test the behavior.

Fixes #8098. Use the fast document.head when available. Don't set unneeded "script.type = text/javascript".

Fixes #8125. Status is set to 200 for requests with status 0 when location.protocol if "file:". Added test/localfile.html to control it works.

Fixes #8095. Properly handles the case where browser cache needs to be bypassed while server-side logic still delivers proper 304 responses. Unit test added.

Makes sure jsonp callback is not left in the global namespace in case of an early abort (beforeSend). Unit test added.

Makes sure all converters keys are lowercased before any conversion is taking place: dataTypes' names are now truly case insensitive. Unit test edited.

Fixes #7568. Follow-up fix for #5862. Objects with a length property weren't serialized properly by jQuery.param.

Adds an invert method to promises that returns a "inverted" promise that is resolved when the underlying deferred is rejected and rejected when the underlying deferred is resolved.