Send message to launcher renderer to update grid (3/3)

This CL supports external surface view callbacks to send messages to
update the launcher's preview grid.

Bug: 348664593
Test: Manually tested. See bug.
Flag: com.android.systemui.shared.new_customization_picker_ui
Change-Id: I8108ae2c49af6b4fc1a207c6ece23e82616baa61
3 files changed