coral: add suppression context to the desk template

To write suppression context in the desk template, we add a data field
to save the tab and app entities of the group. The reasons we should
save all entities instead of getting tab and app info from the restore
data are:

1. the app IDs used by Coral and restore data are different.
2. the web apps' titles used by Coral and restore data are different.

Due to those reasons, directly saving the tab and app entities in
desk template when it is a Coral type template will be easier.

Test: unit test + manual test
Bug: b:385040217
Change-Id: Idcdc85cef8ecc7259b619faf0782d5538f2aa61e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6330123
Reviewed-by: April Zhou <aprilzhou@google.com>
Reviewed-by: Sammie Quon <sammiequon@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Commit-Queue: Xiaodan Zhu <zxdan@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1430946}