Add support for setSystemSelectionChannels

Create API plumbing for setSystemSelectionChannels.
Also update testapps to handle calling the method through the testapp.

Bug: 144595103
Test: manual, atest TelephonyManagerTest
Change-Id: I2dcffb3e5100cb4bfac23e82c9b26fa42c2d5c31
Merged-In: I2dcffb3e5100cb4bfac23e82c9b26fa42c2d5c31
2 files changed