Jank callback API refactor.

Removes the old work-arounds for missing jank callbacks.
Removes the jank data from the transaction completed callback.
Adds new function to ISurfaceComposer to register jank listeners.

With the new API, jank data is only sent over binder periodically
(every ~50 frames) and on a background thread. It is also only tracked
for layers where there is a listener registered.

Test: manual, libsurfaceflinger_unittest
Bug: http://b/336461947
Flag: EXEMPT refactor
Change-Id: I6637a11a6236fdd48998fa63ad823060a0ec3b2a