libvpx: Pull from upstream

source/libvpx/vp8/encoder/ratectrl.c

Index: source/libvpx/vp8/encoder/ratectrl.c
===================================================================
--- source/libvpx/vp8/encoder/ratectrl.c	(revision 240950)
+++ source/libvpx/vp8/encoder/ratectrl.c	(working copy)
@@ -174,14 +174,6 @@
     600, 600, 600, 600, 600, 600, 600, 600,
 };
 
-/* % adjustment to target kf size based on seperation from previous frame */
-static const int kf_boost_seperation_adjustment[16] =
-{
-    30,   40,   50,   55,   60,   65,   70,   75,
-    80,   85,   90,   95,  100,  100,  100,  100,
-};
-
-
 static const int gf_adjust_table[101] =
 {
     100,
@@ -956,6 +948,21 @@
             if (cpi->bits_off_target > cpi->oxcf.maximum_buffer_size)
               cpi->bits_off_target = (int)cpi->oxcf.maximum_buffer_size;
             cpi->buffer_level = cpi->bits_off_target;
+
+            if (cpi->oxcf.number_of_layers > 1) {
+              unsigned int i;
+
+              // Propagate bits saved by dropping the frame to higher layers.
+              for (i = cpi->current_layer + 1; i < cpi->oxcf.number_of_layers;
+                  i++) {
+                LAYER_CONTEXT *lc = &cpi->layer_context[i];
+                lc->bits_off_target += (int)(lc->target_bandwidth /
+                                             lc->framerate);
+                if (lc->bits_off_target > lc->maximum_buffer_size)
+                  lc->bits_off_target = lc->maximum_buffer_size;
+                lc->buffer_level = lc->bits_off_target;
+              }
+            }
         }
     }
 
@@ -1223,7 +1230,6 @@
         {
             Q = cpi->oxcf.gold_q;
         }
-
     }
     else
     {