jquery/jquery-mobile — pull request #6445 by hyunsook (2013-09-06 09:54:06+00:00)
Title: Reducing $.extend function calls to improve performance.

My team is developing Tizen Web UIFW using jQuery Mobile and got a few performance issues.
I told Gabriel and Jasper, and Gabriel ask me to upload this item improved performance.

The current Tizen Web UIFW support jQM-1.2.0 and jQuery-1.8.2.
$.extend is repeatedly called 406 times in Tizen Demo App. using Tizen Web UIFW.
So, I thought that it would be better to cut down and fix the function call count in performance view.

To resolve the issue, my team made progress the task removing $.extend funtion calls in jQM-1.2.0.
We removed $.extend funtion calls in jQM-1.2.0 as much as possible so as not to increase the code lines and get worse performance.
As a result, we could get a good result that although $.extend call time was decreased 11 times, the startup time of Tizen Demo App. was decreased about 64 msec.

Here are jsPerf URLs. You can see the results for several cases of all $.extend function call cases:
Case1. http://jsperf.com/extend-this-vs-direct-setting
Case2. http://jsperf.com/extend-vs-direct-setting/2
Case3. http://jsperf.com/extend-vs-direct-setting-object

At first, I'll upload some modules of jQM 1.4.0 applyed the Case3.
Please look into my codes and If jQM team accepts my PR, I will do a PR again with the other cases.
And it's the first for me to submit a PR. If there are any problems or mistakes to review it, please let me know.