Replaced first pass with a function

Summary: Added a function which does the first pass to determine the free space based on flex items whose min and max constraints are triggered

Reviewed By: emilsjolander

Differential Revision: D6819719

fbshipit-source-id: e5e77c21d1dca2255433da3388887d9db3f7b642

yoga/Utils.h

@@ -44,6 +44,7 @@ struct YGCollectFlexItemsRowValues {
   float totalFlexShrinkScaledFactors;
   float endOfLineIndex;
   std::vector<YGNodeRef> relativeChildren;
+  float remainingFreeSpace;
 };
 
 bool YGValueEqual(const YGValue a, const YGValue b);