Tests: Add Manhattan 3.1 trace Note: This trace is longer than most at 100 frames. This is to help get more accurate data on how transform feedback is behaving. It also allows us the opportunity to trim to smaller sections if we wish, and get more reliable results on unstable systems. Test: angle_perftests --gtest_filter="*manhattan_31*" Bug: angleproject:5589 Bug: angleproject:5591 Change-Id: I76db8a56832d04ea4d335bd81ff98ba1679add5f Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2659850 Reviewed-by: Tim Van Patten <timvp@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Cody Northrop <cnorthrop@google.com>