Add support for serializing a FormData structure that has no elements.  This is important for supporting cached form submissions of empty data, which occurs with some sites like Gmail.
Add support for serializing a FormData structure that has no elements.  This is
important for supporting cached form submissions of empty data, which occurs
with some sites like Gmail.

R=sky

Review URL: http://codereview.chromium.org/56011

git-svn-id: http://src.chromium.org/svn/trunk/src@12711 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 85bd4b5aa039c3c56b582185b2dc7bc3bcb196b8
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