Forward tunnel peek flag to OMX implementation

This commit is part of the video peek in tunnel mode effort. It
forwards the video peek parameter set in MediaCodec APIs to the
underlying OMX codec implementation.

Bug: 157501309
Test: The aforementioned bug tracks the addition of a battery of new
      tunnel mode related CTS tests
Change-Id: Ib0b7266167777d8f66d82d3700e12a9cbb2a99b7