Fix encode perf test

The accepted range changed to -8..8.
BUG:https://code.google.com/p/webm/issues/detail?id=901

Change-Id: I53ac80b58f4819b82c76db61db5dc476f821191f
Revert "Removal of legacy zbin_extra / zbin_oq_value."

This reverts commit e9b586e21bb899e247346e82bccf5afb42604910.

Change-Id: I5b36e6727da6c05278d97e2c37b80c109f79bed4
Merge "Fix encode perf test"