Support retrieve chat past sessions for review

3.5+ site (test on phone and tablet) Access https://mobile36.moodledemo.net/ Go to MoodleMobile Developer Testing Course Go to the Chat section. In the header menu, enable "Show download options". Press the download button and wait until download finishes. Switch to offline. Access the chat activity and press the button "View passed sessions" . Check that some sessions are displayed with: the start date, the duration and the list of participants with the count of messages sent. On tablets a split view is displayed with session on the left and the messages of the first session on the right. Enable "Show incomplete sessions". Check that more sessions are displayed, even if they don't have participants. Go to a session with messages and check that the list of messages is displayed. Switch to online and check than Pull to Refresh works in the list of sessions and the list of messages. 3.4 site (test on any device) Access https://mobile34.next.moodle.com Go to MoodleMobile Developer Testing Course Go to the Chat section. In the header menu, enable "Show download options". Check the download button is NOT displayed next to the chat activity. Open the chat activity. Check that that the button "View passed sessions" is NOT displayed.