Debug RILJ wakelocks on Smdk4210Ril:

Original author's commit message:
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There is a battery drain due to a wakelock being held for an unspecified
length of time. BetterBatteryStats shows it to be RILJ holding the wakelock.
I've narrowed it down to a RIL request named RIL_REQUEST_SET_TTY_MODE. I
dumped out RILJ.mRequestsList during the held wakelock and I see this request
staying around and waiting for a response from the RIL. It's as if the RIL
is not responding to this request and I don't see RILReceiver processing a
response to this request.

One thing to note is that RIL_REQUEST_SET_TTY_MODE is generated when we see
EVENT_TTY_PREFERRED_MODE_CHANGED from PhoneApp. This happens when the phone
boots up and also when you plug in a pair of headphones. Thus this wakelock
can be reproduced by plugging in a pair of headphones.

To work around this, I've added logic to perform a lazy removal of RILRequests
that haven't received a response in the existing wake lock timeout
(60 seconds.)  The removal itself is done as part of
findAndRemoveRequestFromList().  Since new RIL requests are appended to this
list, we're guaranteed that the stale TTY requests will eventually be removed
either when the existing timeout fires, or through this new lazy removal
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Additional comments from Andrew Dodd:

There seem to be all sorts of things that can cause similar behavior.

Rather than purge requests known to have issues, we just print them
so we can fix root cause.

Change-Id: I0a80ba8fb5a1811ab1d8f78e3b8d1bcbfc627377