Revert "Extract network observer code from NetworkManagementService."

This reverts commit d8bc829a85c9c9bb390e18b59ef1455b6d0b94ec.

Reason for revert: Refactoring was unnecessary

Merged-In: Ib4e7da3274e49f25676505a08e6ce7e7b0dfdb8d
Change-Id: Iff332c680315b560f0b762c1d7311ec83d539115
2 files changed