Fix compile warning implicit type conversion.

BUG=aomedia:2461

Change-Id: I0a0003df8310d9550aaf3015eba8c335c6ef4649
diff --git a/av1/encoder/svc_layercontext.c b/av1/encoder/svc_layercontext.c
index 6851422..ef06d10 100644
--- a/av1/encoder/svc_layercontext.c
+++ b/av1/encoder/svc_layercontext.c
@@ -78,11 +78,11 @@
 
 // Update the layer context from a change_config() call.
 void av1_update_layer_context_change_config(AV1_COMP *const cpi,
-                                            const int target_bandwidth) {
+                                            const int64_t target_bandwidth) {
   const RATE_CONTROL *const rc = &cpi->rc;
   SVC *const svc = &cpi->svc;
   int layer = 0;
-  int spatial_layer_target = 0;
+  int64_t spatial_layer_target = 0;
   float bitrate_alloc = 1.0;
 
   for (int sl = 0; sl < svc->number_spatial_layers; ++sl) {
@@ -139,7 +139,7 @@
     LAYER_CONTEXT *const lcprev = &svc->layer_context[prev_layer];
     const double prev_layer_framerate =
         cpi->framerate / lcprev->framerate_factor;
-    const int prev_layer_target_bandwidth = lcprev->layer_target_bitrate;
+    const int64_t prev_layer_target_bandwidth = lcprev->layer_target_bitrate;
     lc->avg_frame_size =
         (int)((lc->target_bandwidth - prev_layer_target_bandwidth) /
               (lc->framerate - prev_layer_framerate));
diff --git a/av1/encoder/svc_layercontext.h b/av1/encoder/svc_layercontext.h
index 01d3fdc..124b8c0 100644
--- a/av1/encoder/svc_layercontext.h
+++ b/av1/encoder/svc_layercontext.h
@@ -22,11 +22,11 @@
 typedef struct {
   RATE_CONTROL rc;
   int framerate_factor;
-  int layer_target_bitrate;
+  int64_t layer_target_bitrate;
   int scaling_factor_num;
   int scaling_factor_den;
-  int target_bandwidth;
-  int spatial_layer_target_bandwidth;
+  int64_t target_bandwidth;
+  int64_t spatial_layer_target_bandwidth;
   double framerate;
   int avg_frame_size;
   int max_q;
@@ -63,7 +63,7 @@
 
 // Update the layer context from a change_config() call.
 void av1_update_layer_context_change_config(struct AV1_COMP *const cpi,
-                                            const int target_bandwidth);
+                                            const int64_t target_bandwidth);
 
 // Prior to encoding the frame, update framerate-related quantities
 // for the current temporal layer.