Web MIDI: add blink APIs to notify device connection events

Source/modules/webmidi/MIDIPort.cpp

Index: Source/modules/webmidi/MIDIPort.cpp
diff --git a/Source/modules/webmidi/MIDIPort.cpp b/Source/modules/webmidi/MIDIPort.cpp
index 622811e13401d40c28505bab19f7eecea059b5f3..ccf6e971afc67d50b8ac47df028a0d769055c8d6 100644
--- a/Source/modules/webmidi/MIDIPort.cpp
+++ b/Source/modules/webmidi/MIDIPort.cpp
@@ -35,13 +35,14 @@
 
 namespace blink {
 
-MIDIPort::MIDIPort(MIDIAccess* access, const String& id, const String& manufacturer, const String& name, MIDIPortTypeCode type, const String& version)
+MIDIPort::MIDIPort(MIDIAccess* access, const String& id, const String& manufacturer, const String& name, MIDIPortTypeCode type, const String& version, bool active)
     : m_id(id)
     , m_manufacturer(manufacturer)
     , m_name(name)
     , m_type(type)
     , m_version(version)
     , m_access(access)
+    , m_active(active)
 {
     ASSERT(access);
     ASSERT(type == MIDIPortTypeInput || type == MIDIPortTypeOutput);