refactor(live-announcer): run outside NgZone (#10631)
refactor(live-announcer): run outside NgZone (#10631)

Switches to running the timeout from the `LiveAnnouncer` outside the `NgZone`, because it does all of its DOM manipulation directly on the element and it doesn't have to trigger Angular's change detection.
DevVersion/material2,Jefiozie/material2,mmalerba/material2,jelbourn/material2,andrewseguin/material2,jelbourn/material2,angular/components,jelbourn/material2,crisbeto/material2,crisbeto/material2,andrewseguin/material2,josephperrott/material2,DevVersion/material2,mmalerba/material2,Jefiozie/material2,crisbeto/material2,josephperrott/material2,josephperrott/material2,angular/components,crisbeto/material2,Jefiozie/material2,DevVersion/material2,Jefiozie/material2,andrewseguin/material2,jelbourn/material2,DevVersion/material2,andrewseguin/material2,angular/components,mmalerba/material2,Jefiozie/material2,angular/components,mmalerba/material2,andrewseguin/material2,josephperrott/material2,mmalerba/material2,josephperrott/material2,jelbourn/material2,DevVersion/material2