This is a convenience function to set a default Source based on extension_name.
This only works with a subset of extension names.
If extension_name is SOURCE_EXTENSION_ADDRESS_BOOK, the
function sets default_source as the default address book. If default_source is null, the default
address book is reset to the built-in address book.
If extension_name is SOURCE_EXTENSION_CALENDAR, the function
sets default_source as the default calendar. If default_source is null, the default calendar is
reset to the built-in calendar.
If extension_name is SOURCE_EXTENSION_MAIL_ACCOUNT, the
function sets default_source as the default mail account. If default_source is null, the default
mail account is reset to the built-in mail account.
If extension_name is SOURCE_EXTENSION_MAIL_IDENTITY,
the function sets default_source as the default mail identity. If default_source is null, the next
request for the default mail identity will return the mail identity named by the default mail account.
If extension_name is SOURCE_EXTENSION_MEMO_LIST, the
function sets default_source as the default memo list. If default_source is null, the default memo
list is reset to the built-in memo list.
If extension_name is SOURCE_EXTENSION_TASK_LIST, the
function sets default_source as the default task list. If default_source is null, the default task
list is reset to the built-in task list.
For all other values of extension_name, the function does nothing.
| this | |
| extension_name |
an extension name |
| default_source |
an Source, or |