DvrWriteBufferQueue: support buffer resizing

Currently, the buffer resising is implemented at the C API's
implementation level, i.e. it's a pure client side logic out of the core
BufferHubQueue C++/PDX implementation. The logic is similar to
BufferHubQueueProducer's buffer resizing logic.

Other minor changes:
1/ Use ProducerQueueConfig in DisplaySurface as well, and plumb default
width, height, and format to bufferhubd when a BufferHubQueue is created
through a Display Surface.
2/ Added detailed dvr_buffer_queue comments.
3/ Since we now have more and more logic in dvr_buffer_queue, refactored
Dvr{Read,Write}BufferQueue to be C++-styled class.

Bug: 38324405
Test: buffer_hub_queue_producer-test, buffer_hub_queue-test, dvr_api-test
Change-Id: I7186fc04e84eafda46eca316a94739bb3b5c07ca