Remove obsolete action transition code from SaveImageInBackgroundTask

These action intents are now only used via their construction in
ActionIntentCreator.

Bug: 288586463
Bug: 287452614
Flag: NONE
Test: atest, verify that shared transitions to markup/sharesheet still
look correct

Change-Id: Ia0f0767372611b80837e3eb9284d51424589ff64
6 files changed