Shift block shortcuts before KeyGestureController

Current shortcuts can be blocked by priviledged windows like
SysUI gesture education. But this logic is currently in PWM.
After refactoring, key gestures can be captured in IMS, so
need to move this logic to IMS now.

Test: atest InputManagerServiceTests
Bug: 358569822
Flag: EXEMPT refactor
Change-Id: I39db6fe4fb355d435e7e8dce65108e3d7ec81b67