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Verify the text after it's collected. I ran the test 20 times and
couldn't find the stale object exception being thrown.

Bug: 340341450
Bug: 339737008
Test: Manual
Flag: com.google.android.apps.nexuslauncher.enable_inject_private_space_tile

Change-Id: Ib153205db36cdd8b5fba4734b8b68930857659ff