Further CQ, Key frame and ARF changes

This code fixes a bug in the calculation of
the minimum Q for alt ref frames.

It also allows an extended gf/arf interval for sections
of clips that completely static (or nearly so).

Change-Id: I1a21aaa16d4f0578e5f99b13bebd78d59403c73b
diff --git a/vp8/encoder/onyx_int.h b/vp8/encoder/onyx_int.h
index 45fafd5..8a97e98 100644
--- a/vp8/encoder/onyx_int.h
+++ b/vp8/encoder/onyx_int.h
@@ -402,6 +402,7 @@
     int kf_overspend_bits;            // Extra bits spent on key frames that need to be recovered on inter frames
     int kf_bitrate_adjustment;        // Current number of bit s to try and recover on each inter frame.
     int max_gf_interval;
+    int static_scene_max_gf_interval;
     int baseline_gf_interval;
     int gf_decay_rate;
     int active_arnr_frames;           // <= cpi->oxcf.arnr_max_frames