Round size geometry for Button and RichText components.

Summary:
ComponentKit requires all size geometry provided to be rounded to pixel grid. This ensures
that layout will not truncate provided sizes.

Reviewed By: cuva

Differential Revision: D6466875

fbshipit-source-id: 62a480411e7d2354a6879917c42bbf0ee96cdadd

yoga/Yoga.h

@@ -274,4 +274,10 @@ WIN_EXPORT YGConfigRef YGConfigGetDefault(void);
 WIN_EXPORT void YGConfigSetContext(const YGConfigRef config, void *context);
 WIN_EXPORT void *YGConfigGetContext(const YGConfigRef config);
 
+WIN_EXPORT float YGRoundValueToPixelGrid(
+    const float value,
+    const float pointScaleFactor,
+    const bool forceCeil,
+    const bool forceFloor);
+
 YG_EXTERN_C_END