[unity] Add activity and interactions sync settings.

This CL add the activity and interactions sync settings. This allows the
user to control whether event logger is enabled. This is controlled internally
by the sync data type USER_EVENTS.

Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: If32166e4b6d8eb3c25d28a8ada67491721cf59d8
Reviewed-on: https://chromium-review.googlesource.com/1126239
Commit-Queue: Mihai Sardarescu <msarda@chromium.org>
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Reviewed-by: Thomas Tangl <tangltom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#574142}
9 files changed