MagnificationConfig stores the magnification configuration of the
controlling magnifier, such as magnification mode, scale and center
postion.
And MagnificationProcessor uses the config to controll the magnifier for
AccessibilityService.
See
API review doc: go/b200769372
Design doc: go/a11yservice_control_magnification_in_t
The chapter at Proposal A and MagnificationConfig
CTS: ag/15824302
Bug: 199732498
Test: atest AbstractAccessibilityServiceConnectionTest,
atest MagnificationProcessorTest,
atest WindowMagnificationManagerTest,
atest MagnificationConfigTest
Change-Id: I20323865d2efe1b40626f0c86767848733856482
1a07e0dbe7