* Update plugin waking code, fix crash on Oreo devices
In Android Oreo we can't use services without bringing them to the
foreground, i.e. showing icon and following specified lifecycle.
After some consideration the new way was implemented for plugin system.
Plugins will no longer have bound service and instead will do everything
required from within their activities. All background logic that
previously resided in services will now be performed before the activity
has even shown its window. This greatly reduces complexity and cost
associated with bringing service model in accordance with Oreo
guidelines. The only downside to this approach is small flickering
or pause in emulators as activities still expect to show themselves
on start instead of disappearing again.
* Move value to class-level constant
45b6063515