Log the number of objects in a Pack when it is deleted in debug builds to help JS app developers find leaks.
Log the number of objects in a Pack when it is deleted in debug builds to help JS app developers find leaks.

TEST=used it in a JS app to help identify a leak
BUG=none
Review URL: http://codereview.chromium.org/6542028

git-svn-id: http://src.chromium.org/svn/trunk/src@75441 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 702490a282d66296162d09ba0e4b1fdb2c66713e
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