Auto merge of #21591 - Manishearth:channelmergernode, r=ferjm

Implement ChannelMergerNode

partial https://github.com/servo/servo/issues/21558

Haven't yet tested, wanted to get this up as an example for https://github.com/servo/servo/issues/21558

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1 files changed, 17 insertions, 2 deletions

diff --git a/components/script/dom/audionode.rs b/components/script/dom/audionode.rs
index 4690f74245e..5a149dd814f 100644
--- a/components/script/dom/audionode.rs
+++ b/components/script/dom/audionode.rs
@@ -44,9 +44,14 @@ impl AudioNode {
         options: &AudioNodeOptions,
         number_of_inputs: u32,
         number_of_outputs: u32,
-    ) -> AudioNode {
+    ) -> Fallible<AudioNode> {
+        if let Some(c) = options.channelCount {
+            if c == 0 || c > MAX_CHANNEL_COUNT {
+                return Err(Error::NotSupported);
+            }
+        }
         let node_id = context.audio_context_impl().create_node(node_type);
-        AudioNode::new_inherited_for_id(node_id, context, options, number_of_inputs, number_of_outputs)
+        Ok(AudioNode::new_inherited_for_id(node_id, context, options, number_of_inputs, number_of_outputs))
     }
 
     pub fn new_inherited_for_id(
@@ -218,6 +223,11 @@ impl AudioNodeMethods for AudioNode {
                     return Err(Error::NotSupported)
                 }
             }
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelMergerNode) => {
+                if value != 1 {
+                    return Err(Error::InvalidState)
+                }
+            }
             // XXX We do not support any of the other AudioNodes with
             // constraints yet. Add more cases here as we add support
             // for new AudioNodes.
@@ -256,6 +266,11 @@ impl AudioNodeMethods for AudioNode {
                     return Err(Error::NotSupported)
                 }
             }
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelMergerNode) => {
+                if value != ChannelCountMode::Explicit {
+                    return Err(Error::InvalidState)
+                }
+            }
             // XXX We do not support any of the other AudioNodes with
             // constraints yet. Add more cases here as we add support
             // for new AudioNodes.