First step towards moving v8 extensions out of WebCore. 
First step towards moving v8 extensions out of WebCore. 

Adds a registerExtension function available in our WebKit public API. 
Once this is in place, another changelist will include actually using it. 

R=mbelshe,darin


Review URL: http://codereview.chromium.org/39070

git-svn-id: http://src.chromium.org/svn/trunk/src@10868 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 381b13eed63f894ec57c7932a4dc4b424fbc8789
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser