Auto merge of #21712 - Manishearth:analysernode, r=ferjm

Implement AnalyserNode

<s>Needs https://github.com/servo/media/pull/127 to land (and a dependency
update)</s>

r? @ferjm

realtimeanalyser-fft-scaling.html, the test that actually checks for some level of FFT correctness, sadly doesn't work since we don't process nodes not connected to the destination.

However I locally fixed the test to work differently and it passed. We'll fix the processing model eventually.

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1 files changed, 7 insertions, 0 deletions

diff --git a/components/script/dom/baseaudiocontext.rs b/components/script/dom/baseaudiocontext.rs
index dbd821b64fe..514a51f113b 100644
--- a/components/script/dom/baseaudiocontext.rs
+++ b/components/script/dom/baseaudiocontext.rs
@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use dom::analysernode::AnalyserNode;
 use dom::audiobuffer::AudioBuffer;
 use dom::audiobuffersourcenode::AudioBufferSourceNode;
 use dom::audiodestinationnode::AudioDestinationNode;
@@ -9,6 +10,7 @@ use dom::audiolistener::AudioListener;
 use dom::audionode::MAX_CHANNEL_COUNT;
 use dom::bindings::callback::ExceptionHandling;
 use dom::bindings::cell::DomRefCell;
+use dom::bindings::codegen::Bindings::AnalyserNodeBinding::AnalyserOptions;
 use dom::bindings::codegen::Bindings::AudioBufferSourceNodeBinding::AudioBufferSourceOptions;
 use dom::bindings::codegen::Bindings::AudioNodeBinding::{ChannelCountMode, ChannelInterpretation};
 use dom::bindings::codegen::Bindings::AudioNodeBinding::AudioNodeOptions;
@@ -337,6 +339,11 @@ impl BaseAudioContextMethods for BaseAudioContext {
         PannerNode::new(&self.global().as_window(), &self, &PannerOptions::empty())
     }
 
+    /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createanalyser
+    fn CreateAnalyser(&self) -> Fallible<DomRoot<AnalyserNode>> {
+        AnalyserNode::new(&self.global().as_window(), &self, &AnalyserOptions::empty())
+    }
+
     /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createchannelmerger
     fn CreateChannelMerger(&self, count: u32) -> Fallible<DomRoot<ChannelMergerNode>> {
         let mut opts = ChannelMergerOptions::empty();