desktop-exploded-view: Show task header immediately while icons load

This change makes it so that the absence of the task icon or title
doesn't delay showing the task header in the exploded view. Once the
icon and title become available, they will shown.

Flag: com.android.launcher3.enable_desktop_exploded_view
Test: Manual and NexusLauncherTests:com.android.quickstep.recents.ui.mapper.TaskUiStateMapperTest
Bug: 398189296
Change-Id: I15bf9c707ea8a5b7cdfdf8b5910c6cfa0323fd6d
3 files changed