Bionic malloc debug: add a new option "abort_on_error"

This new option causes an abort after malloc debug detects an error.
This allows vendors to get process coredumps to analyze memory for
corruption.

Bug: 123009873
Test: New test cases added for unit tests and config tests.

Change-Id: I6b480af7f747d6a82f61e8bf3df204a5f7ba017f