Extract logic related to dragging bubble bar views to other side

Bubble bar can be pinned to left or right by initiating drag from
different views.
Extract common logic related to dragging and showing a drop target.
BaseBubblePinController can be used by both launcher and shell.

Bug: 330585397
Test: atest WMShellRobolectricTests:BubbleExpandedViewPinControllerTest
Test: atest WMShellMultivalentTestsOnDevice:BubbleExpandedViewPinControllerTest
Change-Id: Ief395f30e60f829c73b89fe9f49369f4fd286b12