AudioBuffer: Revert derive of Default

src/buffer.rs

@@ -64,10 +64,10 @@ pub struct AudioBufferOptions {
 ///
 /// - `cargo run --release --example audio_buffer`
 ///
-#[derive(Clone, Debug, Default)]
+#[derive(Clone, Debug)]
 pub struct AudioBuffer {
-    channels: Vec<ChannelData>,
-    sample_rate: f32,
+    pub(crate) channels: Vec<ChannelData>,
+    pub(crate) sample_rate: f32,
 }
 
 impl AudioBuffer {

src/node/audio_buffer_source.rs

@@ -781,8 +781,12 @@ impl AudioProcessor for AudioBufferSourceRenderer {
                 // Avoid deallocation in the render thread by swapping the buffers.
                 std::mem::swap(current_buffer, buffer);
             } else {
-                // The default buffer is empty and does not cause allocations.
-                self.buffer = Some(std::mem::take(buffer));
+                // Creating the tombstone buffer does not cause allocations.
+                let tombstone_buffer = AudioBuffer {
+                    channels: Default::default(),
+                    sample_rate: Default::default(),
+                };
+                self.buffer = Some(std::mem::replace(buffer, tombstone_buffer));
             }
             return;
         };