Retry and reload until provider is ready after Work Profile is turned on

The external storage takes much longer time after the profile is on.
We will ping to see if the cursor is ready.

When the user switch away from the tab, we will unregister
the handler.

Test: manual
Bug: 151733420
Change-Id: I77c4b755bb0356db78145d16a7abba5aeb4adf2c