Add codegen for core components + land blocking tests

Summary: Changelog: [Internal]

Reviewed By: fkgozali, mdvacca

Differential Revision: D18505903

fbshipit-source-id: 9de45c3f8591efaf1be7e2a21fe7d6c77965dc8f

React/Fabric/Mounting/ComponentViews/SafeAreaView/RCTSafeAreaViewComponentView.mm

@@ -9,6 +9,7 @@
 
 #import <react/components/safeareaview/SafeAreaViewComponentDescriptor.h>
 #import <react/components/safeareaview/SafeAreaViewState.h>
+#import "FBRCTFabricComponentsPlugins.h"
 #import "RCTConversions.h"
 #import "RCTFabricComponentsPlugins.h"
 

React/Fabric/Mounting/RCTComponentViewFactory.mm

@@ -73,13 +73,6 @@ using namespace facebook::react;
         [componentViewFactory registerComponentViewClass:klass];
         return;
       }
-    } else {
-      // Fallback 2: In case delegate isn't defined, look into core components.
-      Class<RCTComponentViewProtocol> klass = RCTFabricComponentsProvider(requestedComponentName);
-      if (klass) {
-        [componentViewFactory registerComponentViewClass:klass];
-        return;
-      }
     }
 
     // Fallback 3: Try to use Paper Interop.