Add JavaScript bindings for YGHasNewLayout (#1631)

Summary:
Adds JavaScript bindings for YGHasNewLayout which introduces
two new node methods: `hasNewLayout()` and `markLayoutSeen()`.

Closes https://github.com/facebook/yoga/issues/681

Pull Request resolved: https://github.com/facebook/yoga/pull/1631

Reviewed By: joevilches

Differential Revision: D55213296

Pulled By: NickGerleman

fbshipit-source-id: 161288c3f54c2b82a6b2b842387916fe8713c2c9

javascript/src/Node.cpp

@@ -421,6 +421,14 @@ bool Node::isDirty(void) const {
   return YGNodeIsDirty(m_node);
 }
 
+void Node::markLayoutSeen() {
+  YGNodeSetHasNewLayout(m_node, false);
+}
+
+bool Node::hasNewLayout(void) const {
+  return YGNodeGetHasNewLayout(m_node);
+}
+
 void Node::calculateLayout(double width, double height, int direction) {
   YGNodeCalculateLayout(
       m_node, width, height, static_cast<YGDirection>(direction));