Revert "Update NetworkAgent#register to compatible with old NetworkAgentTest"

This reverts commit 1e7c4a494d89f9a1bd24f1eeca42f7e6a434fea8.

This change is a suspect for causing test breakages, it may or may not be reverted.

Bug: 314087796

Reason for revert: 314087796

Change-Id: If0a1c1e2d0e260319cf64b2d00828638abebb7fe
2 files changed