How do I change the IMAP folder limit for Google Apps and Gmail?

To change the IMAP folder limit in Gmail or Google Apps accounts, go to the Gmail settings page and change the Folder Size Limits section to:

Do not limit the number of messages in an IMAP folder (default)
Make sure IMAP is enabled

Shows the Settings screen. Under the IMAP Access section, there's an arrow pointing to the first option under Folder Size Limits (Do not limit the number of messages...).