Merge "NetworkStats: Avoid Division By 0" am: e22278838e am: 538771303d am: 6dd8eab0f0

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1810678

Change-Id: I0b98a671be9c649f8e0d0655e2820b2430d0a3ef