windows: Add UMA metrics for first-run bubble. 
windows: Add UMA metrics for first-run bubble. 

So we will know which of the buttons the user clicked on. 

BUG=23643
TEST=none 

Patch from Thiago Farina <thiago.farina@gmail.com> 

TBR=ben
Review URL: http://codereview.chromium.org/975002

git-svn-id: http://src.chromium.org/svn/trunk/src@41612 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: b0a581168164eba21af1f8eea2e8188183b0d8c6
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