remove getInstanceCount usages

Summary:
This diffs removes the usages of getInstanceCount as it has been removed from yoga.
We will add event support in js later to handle these test cases

Reviewed By: davidaurelio

Differential Revision: D16560269

fbshipit-source-id: 52590c426faf87209f8635602b401fd5760af8ab

javascript/sources/nbind.cc

@@ -11,14 +11,9 @@
 #include "./Size.hh"
 #include "./Value.hh"
 #include "./Config.hh"
-#include "./global.hh"
 
 #include <nbind/nbind.h>
 
-NBIND_GLOBAL() {
-  function(getInstanceCount);
-}
-
 NBIND_CLASS(Size) {
   construct<>();
   construct<double, double>();