Added several changes in data stack

1. Prepared for removing the old data stack.
2. Fixed minor bugs.
3. Enhanced DataNetworkController callback.
4. Supported overall internet state.

Bug: 196597630
Test: Manual
Merged-In: I99a833caac2f6f47a1fb6d050900c8fb2db3a8e3
Change-Id: I99a833caac2f6f47a1fb6d050900c8fb2db3a8e3
1 file changed