Keep AudioSourceNode from premature GC with ScriptWrappable::hasPendingActivity()

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

Index: third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp b/third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp
index 8823d9dbdba8cc94ef11b5ff2bd0dbb5b946adf1..460eded87107012bf84d023c665254aa1fe80be3 100644
--- a/third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp
+++ b/third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp
@@ -263,5 +263,17 @@ void AudioScheduledSourceNode::setOnended(PassRefPtrWillBeRawPtr<EventListener>
     setAttributeEventListener(EventTypeNames::ended, listener);
 }
 
+bool AudioScheduledSourceNode::hasPendingActivity() const
+{
+    // To avoid the leak, a node should be collected regardless of its
+    // playback state if the context is closed.
+    if (context()->isContextClosed())
+        return false;
+
+    // If a node is scheduled or playing, do not collect the node prematurely
+    // even its reference is out of scope. Then fire onended event if assigned.
+    return audioScheduledSourceHandler().isPlayingOrScheduled();
+}
+
 } // namespace blink