As of Angular v4, four of the options for
`ExtraOptions#initialNavigation` have been deprecated. We intend
to remove them in v11. The final state for these options is:
`enabledBlocking`, `enabledNonBlocking`, and `disabled`. We plan
to remove and deprecate the remaining option in the next two
major releases.
New options:
- `enabledNonBlocking`: same as legacy_enabled
- `enabledBlocking`: same as enabled
BREAKING CHANGE:
* The `initialNavigation` property for the options in
`RouterModule.forRoot` no longer supports `legacy_disabled`,
`legacy_enabled`, `true`, or `false` as valid values.
`legacy_enabled` (the old default) is instead `enabledNonBlocking`
* `enabled` is deprecated as a valid value for the
`RouterModule.forRoot` `initialNavigation` option. `enabledBlocking`
has been introduced to replace it
PR Close#37480
c4becca0e4