Provides actions for editing window magnifier

Providing increasing and decreasing window magnifier size horizontally and vertically actions in window magnification to adjust the window in edit mode in Accessibility Service.
The Talkback actions will only show when they are available.

Bug: 274735988
Test: manually - attach video to the bug
Test: atest WindowMagnificationControllerTest
Change-Id: Ic04e61ae1334b910152aee1fb9056d50e4b832ba