Fix a subtle issue in re-use inter_pred

The initialization of this_mode_pred does not work when the ref_frame
loop ever goes beyond LAST_FRAME. This commit fixes the subtle issue
and allows potentially expanding the loop to test GOLDEN_FRAME.

Change-Id: Ibbd427a22160d1d9eacb8ed0c87f88d6cef9c0f3
1 file changed