make do_sleep pub & add a "stuff the buffer with silence" method useful when you wish to pause an interactive emulator

ferretro_components/src/provided/sdl2/audio.rs

@@ -101,6 +101,10 @@ impl SimpleSdl2AudioComponent {
         }
     }
 
+    pub fn silence_buffer(&self) {
+        let _ = self.audio_sender.try_send(vec![0; self.audio_spec.samples as usize * self.audio_spec.channels as usize]);
+    }
+
     fn send_audio_samples(&mut self) {
         let stereo_samples = self.audio_spec.samples as usize * 2;
         while self.audio_buffer.len() >= stereo_samples {

ferretro_components/src/provided/stdlib.rs

@@ -251,7 +251,7 @@ impl SleepFramerateLimitComponent {
         }
     }
 
-    fn do_sleep(&mut self) {
+    pub fn do_sleep(&mut self) {
         // similar hack to the sample rate, make sure we don't divide by zero.
         let mut spf = 1.0 / self.fps;
         if spf.is_nan() || spf.is_infinite() {