Add sysexEnabled readonly attribute to MIDIAccess

Source/modules/webmidi/MIDIController.h

Index: Source/modules/webmidi/MIDIController.h
diff --git a/Source/modules/webmidi/MIDIController.h b/Source/modules/webmidi/MIDIController.h
index 1644569fd2103f100fca05d4c81c5824f2e439d4..3e0a9de7128834f429a7c7a31676a1986e032ca9 100644
--- a/Source/modules/webmidi/MIDIController.h
+++ b/Source/modules/webmidi/MIDIController.h
@@ -43,8 +43,8 @@ class MIDIController FINAL : public Supplement<Page> {
 public:
     virtual ~MIDIController();
 
-    void requestSysExPermission(PassRefPtrWillBeRawPtr<MIDIAccess>);
-    void cancelSysExPermissionRequest(MIDIAccess*);
+    void requestSysexPermission(PassRefPtrWillBeRawPtr<MIDIAccess>);
+    void cancelSysexPermissionRequest(MIDIAccess*);
 
     static PassOwnPtr<MIDIController> create(MIDIClient*);
     static const char* supplementName();