Fix flaky case testManageExternalStorageCanCreateFilesAnywhere

Use allowAppOpsToUid instead of adoptShellPermissionIdentity to get All
Files Access. This seemed to fix the flake, and is also more suitable
for testing All Files Access since most apps will get the access by
being allowed the app-op rather than getting the permission.

Test: atest FuseDaemonHostTest --iterations 10
Fix: 150081384
Change-Id: I9013434d56e587e3afd29eb79f20b9ffa930e6cf
1 file changed