Move smart actions support code.

Not exercised in AOSP, simplify the AOSP ScreenshotActionsProvider to
just supply the supported actions.

Bug: 329659738
Test: atest DefaultScreenshotActionsProviderTest
Flag: ACONFIG com.android.systemui.screenshot_shelf_ui DEVELOPMENT
Change-Id: I9799b8e4312e8d834f50edb2317690aac787dc9d
Merged-In: I9799b8e4312e8d834f50edb2317690aac787dc9d