Add 'save details in chrome' checkbox.

But only show it when something is actually being edited. Eventually we will also hide it when we're not using autofill, but right now we're always using autofill.

BUG=157273


Review URL: https://chromiumcodereview.appspot.com/12016031

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@178152 0039d316-1c4b-4281-b951-d872f2087c98
8 files changed