base

Add binder transaction tracking.

Add the ability to am to be able to track binder transact calls. This
will help us diagnose excessive IPC calls.

This CL adds the trace-ip command to am. The usage is,

To start binder transaction tracking,
am trace-ipc start
To stop tracking and dump the data to a file,
am trace-ipc stop --dump-file <FILE>

Bug: 21398706
Change-Id: Ic0c9b3be757dd0662a2750a0d8447e2a5ef1fa90