Properly delete the unused policy in password_manager_handler_unittest.cc

ui::SelectFilePolicy* passed to the SelectFileDialog creation methods are
assumed to be owned by the callee (they should ultimately end up in
SelectFileDialog::select_file_policy_, which is a unique_ptr). However,
the test factory in password_manager_handler_unittest.cc ignores the policy
it gets without deleting it. This CL deletes the ignored policy and removes
the leak annotations.

BUG=341477

Review URL: https://codereview.chromium.org/1898143002

Cr-Commit-Position: refs/heads/master@{#388458}
3 files changed