Copy less when active map is in use

When active map is specified and the current frame is not a key frame,
golden frame nor a altref frame then copy only those active regions.

This significantly reduces encoding time by as much as 19% on the test
system where realtime encoding is used. This is particularly useful
when the frame size is large (e.g. 2560x1600) and there's only a few
action macroblocks.

Change-Id: If394a813ec2df5a0201745d1348dbde4278f7ad4

vp8/encoder/onyx_if.c

@@ -4676,7 +4676,7 @@ int vp8_receive_raw_frame(VP8_PTR ptr, unsigned int frame_flags, YV12_BUFFER_CON
 
     vpx_usec_timer_start(&timer);
     if(vp8_lookahead_push(cpi->lookahead, sd, time_stamp, end_time,
-                          frame_flags))
+                          frame_flags, cpi->active_map_enabled ? cpi->active_map : NULL))
         res = -1;
     cm->clr_type = sd->clrtype;
     vpx_usec_timer_mark(&timer);