Merge "Remove unused libbacktrace library." am: f7e6b7f424 am: 341de04dee am: 1b8a6843d6 am: d577354b20 am: a0d72de861

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1807719

Change-Id: Ief535876e6b5a0fd19e2eb1b48b0fa4bfd749b53