Protect apps from ptrace by other system components

The Android security model guarantees the confidentiality and integrity
of application data and execution state. Ptrace bypasses those
confidentiality guarantees. Disallow ptrace access from system components
to apps. Crash_dump is excluded, as it needs ptrace access to
produce stack traces.

Bug: 111317528
Test: code compiles
Change-Id: I883df49d3e9bca62952c3b33d1c691786dd7df4d