Use the cached layout wrapper if it exists

Summary:
- We cache the layout wrapper, but never used it actually.
- This should make the Layout plugin faster.

Reviewed By: fabiomassimo

Differential Revision: D15046463

fbshipit-source-id: b61f28d9a981e782b76abe78037d37665f7d8ba3

iOS/Plugins/FlipperKitLayoutPlugin/FlipperKitLayoutComponentKitSupport/SKComponentLayoutWrapper.mm

@@ -45,12 +45,21 @@ static CKFlexboxComponentChild findFlexboxLayoutParams(CKComponent *parent, CKCo
 
 + (instancetype)newFromRoot:(id<CKInspectableView>)root {
   const CKComponentLayout layout = [root mountedLayout];
+  // Check if there is a cached wrapper.
+  if (layout.component) {
+    SKComponentLayoutWrapper *cachedWrapper = objc_getAssociatedObject(layout.component, &kLayoutWrapperKey);
+    if (cachedWrapper) {
+      return cachedWrapper;
+    }
+  }
   CKComponentReuseWrapper *reuseWrapper = CKAnalyticsListenerHelpers::GetReusedNodes(layout.component);
+  // Create a new layout wrapper.
   SKComponentLayoutWrapper *const wrapper =
   [[SKComponentLayoutWrapper alloc] initWithLayout:layout
                                           position:CGPointMake(0, 0)
                                          parentKey:[NSString stringWithFormat: @"%p.", layout.component]
                                       reuseWrapper:reuseWrapper];
+  // Cache the result.
   if (layout.component) {
     objc_setAssociatedObject(layout.component, &kLayoutWrapperKey, wrapper, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
   }