Move fromStableParcelable to KeepaliveController

TcpKeepaliveController is the only user of
KeepalivePacketDataUtil.fromStableParcelable. Because of
fromStableParcelable, networkstack-client needs to depend on
net-utils-framework-commonm, which pulls a lot of unnecessary classes.
This is particularly problematic considering that networkstack-client
may need to be redistributed as a prebuilt.

Move the method to TcpKeepaliveController, simplifying dependencies.
This also shows that fromStableParcelable could be removed altogether
(or moved to tests) if TcpKeepaliveController built a
TcpKeepalivePacketData class directly.

Test: atest ConnectivityCoverageTests
Change-Id: I554318f6bcd07c73d153598a0231e9fcaf912e90
2 files changed