Add network properties to libsysprop

Since ConnectivityService is going to become a mainline module, it
cannot use SystemProperties.set() to control the tcp init rwnd
value. Thus, create NetworkProperties and add it into libsysprop
to support the usages.

Bug: 170917042
Test: 1. m PlatformProperties-dump-api
      2. replace PlatformProperties-current.txt
      3. make
Change-Id: I3e9a4c3d61afa6c645ebc082493ca4a2d450e42c
2 files changed
tree: c180f0ac587eb2cfce8cac159a709a2ed71dbebc
  1. srcs/
  2. OWNERS