Allow lazy resolution of edge dimension values (#1453)

Summary:
X-link: https://github.com/facebook/react-native/pull/41347

Pull Request resolved: https://github.com/facebook/yoga/pull/1453

This follows the previous patterns used for `Gutters` and `Dimension`, where we hide CompactValue array implementation from `yoga::Style` callers.

This allows a single read of a style to only need access to the resolved values of a single edge, vs all edges. This is cheap now because the interface is the representation, but gets expensive if `StyleValuePool` is the actual implementation.

This prevents us from needing to resolve nine dimensions, in order to read a single value like `marginLeft`. Doing this, in the new style, also lets us remove `IdxRef` from the API.

We unroll the structure dependent parts in the props parsing code, for something more verbose, but also a bit clearer.

Changelog: [Internal]

Reviewed By: joevilches

Differential Revision: D50998164

fbshipit-source-id: 248396f9587e29d62cde05ae7512d8194f60c809

yoga/node/Node.h

@@ -65,6 +65,12 @@ class YG_EXPORT Node : public ::YGNode {
     style_.alignContent() = Align::Stretch;
   }
 
+  template <auto Field>
+  CompactValue computeEdgeValueForColumn(YGEdge edge) const;
+
+  template <auto Field>
+  CompactValue computeEdgeValueForRow(YGEdge rowEdge, YGEdge edge) const;
+
   // DANGER DANGER DANGER!
   // If the node assigned to has children, we'd either have to deallocate
   // them (potentially incorrect) or ignore them (danger of leaks). Only ever
@@ -189,15 +195,6 @@ class YG_EXPORT Node : public ::YGNode {
     return resolvedDimensions_[static_cast<size_t>(dimension)];
   }
 
-  static CompactValue computeEdgeValueForColumn(
-      const Style::Edges& edges,
-      YGEdge edge);
-
-  static CompactValue computeEdgeValueForRow(
-      const Style::Edges& edges,
-      YGEdge rowEdge,
-      YGEdge edge);
-
   // Methods related to positions, margin, padding and border
   bool isFlexStartPositionDefined(FlexDirection axis) const;
   bool isInlineStartPositionDefined(FlexDirection axis, Direction direction)