Various updates to vp8.

Change-Id: Icc7a816491897107764e4c936288e9000e6319b8
diff --git a/vp8/encoder/ratectrl.c b/vp8/encoder/ratectrl.c
index c51650c..e30ad9e 100644
--- a/vp8/encoder/ratectrl.c
+++ b/vp8/encoder/ratectrl.c
@@ -708,7 +708,13 @@
                     Adjustment = (cpi->this_frame_target - min_frame_target);
 
                 if (cpi->frames_since_golden == (cpi->current_gf_interval >> 1))
-                    cpi->this_frame_target += ((cpi->current_gf_interval - 1) * Adjustment);
+                {
+                    Adjustment = (cpi->current_gf_interval - 1) * Adjustment;
+                    // Limit adjustment to 10% of current target.
+                    if (Adjustment > (10 * cpi->this_frame_target) / 100)
+                        Adjustment = (10 * cpi->this_frame_target) / 100;
+                    cpi->this_frame_target += Adjustment;
+                }
                 else
                     cpi->this_frame_target -= Adjustment;
             }