Simplify flow of control

Change-Id: Idded8f8774c10c53fba59e7b834583399e57225c

av1/av1_cx_iface.c

@@ -1225,7 +1225,8 @@ static aom_codec_err_t encoder_encode(aom_codec_alg_priv_t *ctx,
         return AOM_CODEC_ERROR;
       }
 #endif
-      if (frame_size) {
+      if (!frame_size) continue;
+
       // Pack invisible frames with the next visible frame
       if (!cpi->common.show_frame) {
         if (ctx->pending_cx_data == 0) ctx->pending_cx_data = cx_data;
@@ -1242,7 +1243,7 @@ static aom_codec_err_t encoder_encode(aom_codec_alg_priv_t *ctx,
 
       pkt.kind = AOM_CODEC_CX_FRAME_PKT;
       pkt.data.frame.pts = ticks_to_timebase_units(timebase, dst_time_stamp);
-        pkt.data.frame.duration = (unsigned long)ticks_to_timebase_units(
+      pkt.data.frame.duration = (uint32_t)ticks_to_timebase_units(
           timebase, dst_end_time_stamp - dst_time_stamp);
       pkt.data.frame.flags = get_frame_pkt_flags(cpi, lib_flags);
 
@@ -1267,7 +1268,6 @@ static aom_codec_err_t encoder_encode(aom_codec_alg_priv_t *ctx,
       cx_data_sz -= frame_size;
     }
   }
-  }
 
   cpi->common.error.setjmp = 0;
   return res;