Disable chatty log trimming on Android

[akoeplinger]

We see quite often in the logcat something like this:

chatty  : uid=10225(net.dot.System.Net.Sockets.Tests) expire 102 lines

The chatty service removes log messages if a process logs too many messages in some time period. This is exactly what our tests do though since we print a line for each passed/failed test 😄

We should disable this behavior by running logcat -P "" before starting the test run.