frameworks/base: Watchdog to generate trace of Monkey

We need stacktrace of Monkey process to debug issues wherein
system_server gets stuck doing a binder call with monkey

Change-Id: Ie0be15662c68219fe5e95592c672b86ab0987e37
(cherry picked from commit c509d1147e321118f1c908502b0b9eb5ee2a5926)

Conflicts:
	services/java/com/android/server/Watchdog.java
frameworks/base: move the traces file to avoid data loss

If an ANR comes just after the framework reboot, the traces for
the framework reboot will get over-written with the ANR traces.
So, We are missing the traces for the framework reboot which
makes debugging the framework reboot difficult.

This patch will rename this trace file for the framework reboot
once the ActivityManager collects the traces.

Change-Id: Iee07b13ba02d8aab9cc43567aa5df131cc43c737

Conflicts:
	services/java/com/android/server/Watchdog.java
frameworks/base: creating sperate files for ANRs traces

If an ANR comes just after the framework reboot, the traces for the
framework reboot will get over-written with the ANR traces. So, We
are missing the traces for the framework reboot which makes debugging
the framework reboot difficult.

Even for multiple ANRs in different apps, we will get the traces for
the last ANR.

Most of the time traces show that the call is stuck in some native call
and we do not have any info about the native call stack becuase we do
not collect the tombstones for teh ANR.

This patch will create one trace file for each application in case of ANR
and the filename would be traces_<app_name>.txt and the traces for
framework reboot will be stored in traces.txt

Change-Id: Iec2daee0350b20571d0bda9330a17a68df194f8b