fix build

Author: Bin Liu

AsyncDisplayKit/ASCollectionNode.h

@@ -18,7 +18,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (instancetype)initWithCollectionViewLayout:(UICollectionViewLayout *)layout;
 - (instancetype)initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout;
-- (instancetype)initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator;
+- (instancetype)initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(nullable id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator;
 
 @property (weak, nonatomic) id <ASCollectionDelegate>   delegate;
 @property (weak, nonatomic) id <ASCollectionDataSource> dataSource;

AsyncDisplayKit/ASCollectionView.h

@@ -13,7 +13,7 @@
 #import <AsyncDisplayKit/ASBaseDefines.h>
 #import <AsyncDisplayKit/ASBatchContext.h>
 #import <AsyncDisplayKit/ASCollectionViewFlowLayoutInspector.h>
-#import <AsyncDisplayKit/ASCollectionViewLayoutFacilitatorProtocol.h>
+#import "ASCollectionViewLayoutFacilitatorProtocol.h"
 
 @class ASCellNode;
 @class ASCollectionNode;