Move close() from BaseAudioContext to AudioContext

OfflineAudioContext cannot be closed so it makes more sense to have
close() be defined on AudioContext instead of BaseAudioContext.

This is a very minor tweak to the API, so no Blink intent submitted.

Spec issue: https://github.com/WebAudio/web-audio-api/issues/948
Resolved:   https://github.com/WebAudio/web-audio-api/issues/974
Chrome feature: https://www.chromestatus.com/feature/5683205155848192

BUG=647261
TEST=audiocontext-close.html

Review-Url: https://codereview.chromium.org/2345693002
Cr-Commit-Position: refs/heads/master@{#419244}

third_party/WebKit/LayoutTests/virtual/stable/webexposed/global-interface-listing-expected.txt

@@ -125,6 +125,7 @@ interface AudioBufferSourceNode : AudioSourceNode
     setter onended
 interface AudioContext : BaseAudioContext
     attribute @@toStringTag
+    method close
     method constructor
 interface AudioDestinationNode : AudioNode
     attribute @@toStringTag
@@ -6236,6 +6237,7 @@ interface XSLTProcessor
     method transformToFragment
 interface webkitAudioContext : BaseAudioContext
     attribute @@toStringTag
+    method close
     method constructor
 interface webkitIDBCursor
     attribute @@toStringTag

third_party/WebKit/LayoutTests/webaudio/audiocontext-close-expected.txt

@@ -33,10 +33,7 @@ PASS Closing context again correctly rejected promise.
 PASS context.destination is null
 PASS offline = new OfflineAudioContext(1, 1000, 48000) did not throw exception.
 PASS offline.state is "suspended"
-PASS Closing offline context correctly rejected: InvalidAccessError: cannot close an OfflineAudioContext.
-PASS Closing offline context again correctly rejected
-PASS offline.startRendering() did not throw exception.
-PASS event.target.state is "closed"
+PASS offline.close is undefined.
 PASS successfullyParsed is true
 
 TEST COMPLETE

third_party/WebKit/LayoutTests/webaudio/audiocontext-close.html

@@ -114,47 +114,11 @@
     // Task: test offline context (1).
     audit.defineTask('test-offline-context-1', function (done) {
 
-      // For an offline context, just check that if we try to close the context,
-      // nothing happens except that the promise returned by close() is rejected.
+      // For an offline context, verify that close is not defined.
       shouldNotThrow("offline = new OfflineAudioContext(1, 1000, 48000)");
       shouldBeEqualToString("offline.state", "suspended");
-      offline.close().then(
-        function () {
-          testFailed("Closing offline context erroneously resolved");
-        },
-        function (e) {
-          if (e.name === "InvalidAccessError") {
-            testPassed("Closing offline context correctly rejected: " + e);
-          } else {
-            testFailed("Closing offline context correctly rejected but expected InvalidAccessError, not: " + e);
-          }
-        }
-      ).then(done);
-    });
-
-    // Task: test offline context (2).
-    audit.defineTask('test-offline-context-2', function (done) {
-
-      // Try closing again
-      offline.close().then(
-        function () {
-          testFailed("Closing offline context again erroneously resolved");
-        },
-        function () {
-          testPassed("Closing offline context again correctly rejected");
-        }
-      ).then(
-        function () {
-
-          // Render the context, and check for a valid state
-          offline.oncomplete = function (event) {
-            shouldBeEqualToString("event.target.state", "closed");
-            done();
-          };
-          shouldNotThrow("offline.startRendering()");
-        }
-      );
-
+      shouldBeUndefined("offline.close");
+      done();
     });
 
     audit.defineTask('finish-test', function (done) {
@@ -162,14 +126,7 @@
       finishJSTest();
     });
 
-    audit.runTasks(
-      'test-online-context-1',
-      'test-online-context-2',
-      'test-online-context-3',
-      'test-offline-context-1',
-      'test-offline-context-2',
-      'finish-test'
-    );
+    audit.runTasks();
 
     successfullyParsed = true;
   </script>

third_party/WebKit/LayoutTests/webexposed/global-interface-listing-expected.txt

@@ -160,6 +160,7 @@ interface AudioBufferSourceNode : AudioSourceNode
     setter onended
 interface AudioContext : BaseAudioContext
     attribute @@toStringTag
+    method close
     method constructor
 interface AudioDestinationNode : AudioNode
     attribute @@toStringTag
@@ -7374,6 +7375,7 @@ interface XSLTProcessor
     method transformToFragment
 interface webkitAudioContext : BaseAudioContext
     attribute @@toStringTag
+    method close
     method constructor
 interface webkitIDBCursor
     attribute @@toStringTag

third_party/WebKit/Source/modules/webaudio/AudioContext.h

@@ -26,7 +26,7 @@ public:
     ~AudioContext() override;
     DECLARE_VIRTUAL_TRACE();
 
-    ScriptPromise closeContext(ScriptState*) final;
+    ScriptPromise closeContext(ScriptState*);
     bool isContextClosed() const final;
 
     ScriptPromise suspendContext(ScriptState*) final;

third_party/WebKit/Source/modules/webaudio/AudioContext.idl

@@ -32,6 +32,9 @@
     NoInterfaceObject,
     RaisesException=Constructor,
 ] interface AudioContext : BaseAudioContext {
+    // Close
+    [MeasureAs=AudioContextClose, CallWith=ScriptState, ImplementedAs=closeContext] Promise<void> close();
+
     // Sources
     // TODO(rtoy): The following methods should be here instead of in BaseAudioContext:
     //

third_party/WebKit/Source/modules/webaudio/BaseAudioContext.h

@@ -176,9 +176,6 @@ public:
     PeriodicWave* createPeriodicWave(DOMFloat32Array* real, DOMFloat32Array* imag, ExceptionState&);
     PeriodicWave* createPeriodicWave(DOMFloat32Array* real, DOMFloat32Array* imag, const PeriodicWaveConstraints&, ExceptionState&);
 
-    // Close
-    virtual ScriptPromise closeContext(ScriptState*) = 0;
-
     // Suspend
     virtual ScriptPromise suspendContext(ScriptState*) = 0;
 

third_party/WebKit/Source/modules/webaudio/BaseAudioContext.idl

@@ -56,9 +56,6 @@ enum AudioContextState {
     [RaisesException, MeasureAs=AudioContextCreateChannelSplitter] ChannelSplitterNode createChannelSplitter(optional unsigned long numberOfOutputs);
     [RaisesException, MeasureAs=AudioContextCreateChannelMerger] ChannelMergerNode createChannelMerger(optional unsigned long numberOfInputs);
 
-    // Close
-    [MeasureAs=AudioContextClose, CallWith=ScriptState, ImplementedAs=closeContext] Promise<void> close();
-
     // Pause/resume
     [MeasureAs=AudioContextSuspend, CallWith=ScriptState, ImplementedAs=suspendContext] Promise<void> suspend();
     [MeasureAs=AudioContextResume, CallWith=ScriptState, ImplementedAs=resumeContext] Promise<void> resume();

third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp

@@ -199,15 +199,6 @@ ScriptPromise OfflineAudioContext::startOfflineRendering(ScriptState* scriptStat
     return m_completeResolver->promise();
 }
 
-ScriptPromise OfflineAudioContext::closeContext(ScriptState* scriptState)
-{
-    return ScriptPromise::rejectWithDOMException(
-        scriptState,
-        DOMException::create(
-            InvalidAccessError,
-            "cannot close an OfflineAudioContext."));
-}
-
 ScriptPromise OfflineAudioContext::suspendContext(ScriptState* scriptState)
 {
     // This CANNOT be called on OfflineAudioContext; this is only to implement

third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.h

@@ -47,7 +47,6 @@ public:
 
     ScriptPromise startOfflineRendering(ScriptState*);
 
-    ScriptPromise closeContext(ScriptState*) final;
     ScriptPromise suspendContext(ScriptState*, double);
     ScriptPromise resumeContext(ScriptState*) final;