Generalize the unhandled drag listener for other global drag callbacks

- Basically rename unhandled drag listener -> global drag listener

Bug: 320797628
Test: atest DragDropTests DragDropControllerTests CrossAppDragAndDropTests
Test: atest WMShellUnitTests
Change-Id: I96d7f7223852af358d45edbe7b0db135944af2b1
8 files changed