Auto merge of #21602 - ferjm:audiobuffer.crash, r=<try>

Fix AudioBuffer crash

- [X] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [X] There are tests for these changes

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components/script/dom/audiobuffer.rs

@@ -135,8 +135,8 @@ impl AudioBuffer {
 
             // Move the channel data from shared_channels to js_channels.
             rooted!(in (cx) let mut array = ptr::null_mut::<JSObject>());
-            let shared_channel = (*self.shared_channels.borrow_mut()).buffers.remove(i);
-            if Float32Array::create(cx, CreateWith::Slice(&shared_channel), array.handle_mut())
+            let shared_channel = &(*self.shared_channels.borrow_mut()).buffers[i];
+            if Float32Array::create(cx, CreateWith::Slice(shared_channel), array.handle_mut())
                 .is_err()
             {
                 return false;
@@ -183,8 +183,6 @@ impl AudioBuffer {
             // data into js_channels ArrayBuffers in restore_js_channel_data.
         }
 
-        self.js_channels.borrow_mut().clear();
-
         Some((*self.shared_channels.borrow()).clone())
     }
 }

tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-playbackrate-zero.html.ini

@@ -1,2 +1,10 @@
 [audiobuffersource-playbackrate-zero.html]
-  expected: CRASH
+  [< [synthesize-verify\] 1 out of 1 assertions were failed.]
+    expected: FAIL
+
+  [X The zero playbackRate should hold the sample value. Expected 0.5 but got 0.5001220703125 at the index 4097 Got false.]
+    expected: FAIL
+
+  [# AUDIT TASK RUNNER FINISHED: 1 out of 1 tasks were failed.]
+    expected: FAIL
+

tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-start.html.ini

@@ -26,3 +26,6 @@
   [# AUDIT TASK RUNNER FINISHED: 1 out of 1 tasks were failed.]
     expected: FAIL
 
+  [< [Tests AudioBufferSourceNode start()\] 6 out of 18 assertions were failed.]
+    expected: FAIL
+

tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/note-grain-on-play.html.ini

@@ -1,2 +1,22 @@
 [note-grain-on-play.html]
-  expected: CRASH
+  [X Number of grains that started at the correct time is not equal to 100. Got 1.]
+    expected: FAIL
+
+  [X Pulse 0 boundary expected to be equal to the array [0,441\] but differs in 1 places:\n\tIndex\tActual\t\t\tExpected\n\t[1\]\t4.8520000000000000e+3\t4.4100000000000000e+2]
+    expected: FAIL
+
+  [X Number of start frames is not equal to 100. Got 1.]
+    expected: FAIL
+
+  [X Number of grains out of 100 that ended at the wrong time is not equal to 0. Got 1.]
+    expected: FAIL
+
+  [< [note-grain-on-play\] 5 out of 8 assertions were failed.]
+    expected: FAIL
+
+  [X Number of end frames is not equal to 100. Got 1.]
+    expected: FAIL
+
+  [# AUDIT TASK RUNNER FINISHED: 1 out of 1 tasks were failed.]
+    expected: FAIL
+

tests/wpt/metadata/webaudio/the-audio-api/the-audionode-interface/audionode-channel-rules.html.ini

@@ -1,2 +1,2 @@
 [audionode-channel-rules.html]
-  expected: CRASH
+  expected: TIMEOUT

tests/wpt/metadata/webaudio/the-audio-api/the-audioparam-interface/audioparam-connect-audioratesignal.html.ini

@@ -1,2 +1,10 @@
 [audioparam-connect-audioratesignal.html]
-  expected: CRASH
+  [# AUDIT TASK RUNNER FINISHED: 1 out of 1 tasks were failed.]
+    expected: FAIL
+
+  [X Rendered signal exactly matches the audio-rate gain changing signal is not true. Got false.]
+    expected: FAIL
+
+  [< [test\] 1 out of 2 assertions were failed.]
+    expected: FAIL
+

tests/wpt/metadata/webaudio/the-audio-api/the-audioparam-interface/audioparam-summingjunction.html.ini

@@ -1,2 +1,10 @@
 [audioparam-summingjunction.html]
-  expected: CRASH
+  [# AUDIT TASK RUNNER FINISHED: 1 out of 1 tasks were failed.]
+    expected: FAIL
+
+  [X Rendered signal matches sum of two audio-rate gain changing signals plus baseline gain is not true. Got false.]
+    expected: FAIL
+
+  [< [test\] 1 out of 2 assertions were failed.]
+    expected: FAIL
+