Enforce calling identity before clearing.

When opening a downloaded file, enforce that the caller can actually
see the requested download before clearing their identity to read
internal columns.

Bug: 30537115
Change-Id: I01bbad7997e5e908bfb19f5d576860a24f59f295
(cherry picked from commit 8be3a92eb0b4105a9ed748be5a937ce79145f565)
1 file changed