Web MIDI: implement implicit open() on send() and setOnmidimessage()

Source/modules/webmidi/MIDIInput.cpp

Index: Source/modules/webmidi/MIDIInput.cpp
diff --git a/Source/modules/webmidi/MIDIInput.cpp b/Source/modules/webmidi/MIDIInput.cpp
index 45da45e39b8ac4e5cc3e3584de1e75edfc0726e7..41d17cf3aa706e00ae7f47b27e92c5ba7cbfcaf0 100644
--- a/Source/modules/webmidi/MIDIInput.cpp
+++ b/Source/modules/webmidi/MIDIInput.cpp
@@ -50,6 +50,19 @@ MIDIInput::MIDIInput(MIDIAccess* access, const String& id, const String& manufac
 {
 }
 
+EventListener* MIDIInput::onmidimessage()
+{
+    return getAttributeEventListener(EventTypeNames::midimessage);
+}
+
+void MIDIInput::setOnmidimessage(PassRefPtr<EventListener> listener)
+{
+    // Implicit open. It does nothing if the port is already opened.

[kouhei (in TOK), 2015/04/02 05:10:52]

Please add a link to the spec for "spec" behaviours.

[Takashi Toyoshima, 2015/04/02 05:25:41]

Done.

+    open();
+
+    setAttributeEventListener(EventTypeNames::midimessage, listener);
+}
+
 void MIDIInput::didReceiveMIDIData(unsigned portIndex, const unsigned char* data, size_t length, double timeStamp)
 {
     ASSERT(isMainThread());
@@ -57,6 +70,9 @@ void MIDIInput::didReceiveMIDIData(unsigned portIndex, const unsigned char* data
     if (!length)
         return;
 
+    if (getConnection() != ConnectionStateOpen)
+        return;
+
     // Drop sysex message here when the client does not request it. Note that this is not a security check but an
     // automatic filtering for clients that do not want sysex message. Also note that sysex message will never be sent
     // unless the current process has an explicit permission to handle sysex message.