Auto merge of #23997 - collares:audiobuffersourcenode, r=ferjm

Implement missing functionality of AudioBufferSourceNode

<!-- Please describe your changes on the following line: -->
This is a tiny PR to support [Media #293](https://github.com/servo/media/pull/293). Last time I ran WPT there was only one failing AudioBufferSourceNode test (which I will debug later this week). Once I rebased, however, I started getting unrelated servo-media build failures:

```
error[E0599]: no method named `shutdown_audio_context` found for type `std::sync::Arc<servo_media::ServoMedia>` in the current scope
   --> components/script/dom/baseaudiocontext.rs:566:14

error[E0599]: no method named `shutdown_player` found for type `std::sync::Arc<servo_media::ServoMedia>` in the current scope
    --> components/script/dom/htmlmediaelement.rs:1866:18
```

I wanted to get this PR up so https://github.com/servo/media/pull/293 can be tested. When the unrelated build failures are fixed, I will run `./mach update-wpt` and update this PR.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [X] `./mach build -d` only reports unrelated errors (broken servo/media master?)
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #22363

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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components/script/dom/audiobuffer.rs

@@ -115,8 +115,11 @@ impl AudioBuffer {
     // Initialize the underlying channels data with initial data provided by
     // the user or silence otherwise.
     fn set_initial_data(&self, initial_data: Option<&[Vec<f32>]>) {
-        let mut channels =
-            ServoMediaAudioBuffer::new(self.number_of_channels as u8, self.length as usize);
+        let mut channels = ServoMediaAudioBuffer::new(
+            self.number_of_channels as u8,
+            self.length as usize,
+            self.sample_rate,
+        );
         for channel in 0..self.number_of_channels {
             channels.buffers[channel as usize] = match initial_data {
                 Some(data) => data[channel as usize].clone(),
@@ -164,8 +167,11 @@ impl AudioBuffer {
     // https://webaudio.github.io/web-audio-api/#acquire-the-content
     #[allow(unsafe_code)]
     fn acquire_contents(&self) -> Option<ServoMediaAudioBuffer> {
-        let mut result =
-            ServoMediaAudioBuffer::new(self.number_of_channels as u8, self.length as usize);
+        let mut result = ServoMediaAudioBuffer::new(
+            self.number_of_channels as u8,
+            self.length as usize,
+            self.sample_rate,
+        );
         let cx = self.global().get_cx();
         for (i, channel) in self.js_channels.borrow_mut().iter().enumerate() {
             // Step 1.

components/script/dom/audiobuffersourcenode.rs

@@ -171,6 +171,10 @@ impl AudioBufferSourceNodeMethods for AudioBufferSourceNode {
     // https://webaudio.github.io/web-audio-api/#dom-audiobuffersourcenode-loop
     fn SetLoop(&self, should_loop: bool) {
         self.loop_enabled.set(should_loop);
+        let msg = AudioNodeMessage::AudioBufferSourceNode(
+            AudioBufferSourceNodeMessage::SetLoopEnabled(should_loop),
+        );
+        self.source_node.node().message(msg);
     }
 
     // https://webaudio.github.io/web-audio-api/#dom-audiobuffersourcenode-loopstart
@@ -181,6 +185,10 @@ impl AudioBufferSourceNodeMethods for AudioBufferSourceNode {
     // https://webaudio.github.io/web-audio-api/#dom-audiobuffersourcenode-loopstart
     fn SetLoopStart(&self, loop_start: Finite<f64>) {
         self.loop_start.set(*loop_start);
+        let msg = AudioNodeMessage::AudioBufferSourceNode(
+            AudioBufferSourceNodeMessage::SetLoopStart(*loop_start),
+        );
+        self.source_node.node().message(msg);
     }
 
     // https://webaudio.github.io/web-audio-api/#dom-audiobuffersourcenode-loopend
@@ -190,7 +198,11 @@ impl AudioBufferSourceNodeMethods for AudioBufferSourceNode {
 
     // https://webaudio.github.io/web-audio-api/#dom-audiobuffersourcenode-loopend
     fn SetLoopEnd(&self, loop_end: Finite<f64>) {
-        self.loop_end.set(*loop_end)
+        self.loop_end.set(*loop_end);
+        let msg = AudioNodeMessage::AudioBufferSourceNode(
+            AudioBufferSourceNodeMessage::SetLoopEnd(*loop_end),
+        );
+        self.source_node.node().message(msg);
     }
 
     // https://webaudio.github.io/web-audio-api/#dom-audiobuffersourcenode-start
@@ -224,6 +236,17 @@ impl AudioBufferSourceNodeMethods for AudioBufferSourceNode {
                     ));
             }
         }
+
+        self.source_node
+            .node()
+            .message(AudioNodeMessage::AudioBufferSourceNode(
+                AudioBufferSourceNodeMessage::SetStartParams(
+                    *when,
+                    offset.map(|f| *f),
+                    duration.map(|f| *f),
+                ),
+            ));
+
         self.source_node
             .upcast::<AudioScheduledSourceNode>()
             .Start(when)