Use bugreport mode enums from BugreportParams

All callers of requestBugReport(enum) have been migrated to use
wrappers, so it's safe to switch the internal enum we use for bugreport
mode from ActivityManager constants to BugreportParams enum.

Note that in requestBugReport() we have been passing ActivityManager
constant enum for INTERACTIVE bugreport, when sending an intent to
Shell, where BugreportPramas enum was expected, but it worked fine
because they had the same value. We can stop relying on that.

Bug: 137825297
Bug: 141355059
Test: Interactive bugreports created successfully
Change-Id: I1ab5d471a6d5c70fcd201719eae90f820e17cb80