Fix 2 bugs that fail to update item listener right.

* Reset SelectionMetadata on model update.
* Stop updating item listener if an item is selected when we try to add
  it to provisional selection.
* Add tests to ensure consistency between SelectionManager and
  ItemCallbacks

Test: Manual tests & auto tests.
Bug: 37083128
Change-Id: I15149c71fa56f38ae5867a13d9026146a969c525
(cherry picked from commit b8874fd0)