jquery/jquery-mobile — pull request #5402 by Changsuk (2012-12-24 08:43:41+00:00)
Title: Reusing "$.mobile.firstPage" variable to improve performance slightly.

"$page.first()" function call is repeated on jquey.mobile.init.js file. "$page.first()" function is already called and assigned to "$.mobile.firstPage" variable. So the variable can be used without duplicated function call. You can know that Javascript Core(JSC) or other Javascript runtime engine will execute $page.first() function once more at that line. So It would be better to use not "$page.first()." but "$.mobile.firstPage."
And there are verified PR steps.

1. Tests : The code has been tested on several jQM widgets using qunit.js.
2. Modified code is followed the jQuery Core Style guide.
3. Scope : Performance improvement.

This is my first PR. If there is any problems to review it, please let me know. Thanks in advance.