The Chrome bug report is here: http://code.google.com/p/chromium/issues/detail?id=45640
The bug there is that Chrome is filling in a control that isn't visible, and, even worse, that it is filling it with a value that the user couldn't himself enter manually. That's a bug (two bugs in fact), but it has nothing to do with reporting validation errors -- the error should not be able to occur.
Please look at the original report and Comment #4. It is not an auto-fill issue. Comment #2 is an auto-fill bug and it was moved to another bug entry. Regardless of the auto-fill bug, we still have compatibility issues and we can't force authors to update their web pages. I'm wondering UA should show a dialog with "The web page has invisible invalid form fields. Do you want to submit the form? [Yes] [No]". -- TAMURA Kent Software Engineer, Google