Update the test app with an option to launch CCTs as separate tasks

This change updates the client example app with an option to launch
CCTs, except for Partial CCTs, as separate tasks. This could be used to
test features such as predictive gesture and how it behaves based on how
it is launched (separate task vs. same activity).

Bug: 40285983
Change-Id: Id741061f9a664a1e5f663face22c22dd14ef5fe9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6449620
Reviewed-by: Theresa Sullivan <twellington@chromium.org>
Commit-Queue: Moe Adel <adelm@google.com>
Reviewed-by: Jinsuk Kim <jinsukkim@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1445604}