[ASLayout] General Layout Cleanup (#2920)

* Remove duplicate import

* Move `ASLayoutController` related code out of CoreGraphics+ASConvenience

* Further cleanup

* Move private layout files to Privat/Layout

* Move ASLayoutElementStylePrivate into Private/Layout

* Further cleanup

* Move tvOS related files to tvOS folder

* Further cleanup

AsyncDisplayKit/Private/ASDisplayNodeLayout.mm

@@ -10,7 +10,7 @@
 //  of patent rights can be found in the PATENTS file in the same directory.
 //
 
-#include "ASDisplayNodeLayout.h"
+#import "ASDisplayNodeLayout.h"
 
 BOOL ASDisplayNodeLayout::isDirty()
 {

AsyncDisplayKit/Private/ASImageNode+CGExtras.h

@@ -8,10 +8,9 @@
 //  of patent rights can be found in the PATENTS file in the same directory.
 //
 
+#import <UIKit/UIKit.h>
 #import <AsyncDisplayKit/ASBaseDefines.h>
 
-#include <UIKit/UIKit.h>
-
 ASDISPLAYNODE_EXTERN_C_BEGIN
 
 

AsyncDisplayKit/Private/ASImageNode+CGExtras.m

@@ -9,6 +9,7 @@
 //
 
 #import "ASImageNode+CGExtras.h"
+
 #import <tgmath.h>
 
 // TODO rewrite these to be closer to the intended use -- take UIViewContentMode as param, CGRect destinationBounds, CGSize sourceSize.

AsyncDisplayKit/Private/ASInternalHelpers.m

@@ -9,13 +9,13 @@
 //
 
 #import "ASInternalHelpers.h"
-#import "ASRunLoopQueue.h"
 
 #import <objc/runtime.h>
-
-#import "ASThread.h"
 #import <tgmath.h>
 
+#import "ASRunLoopQueue.h"
+#import "ASThread.h"
+
 BOOL ASSubclassOverridesSelector(Class superclass, Class subclass, SEL selector)
 {
   if (superclass == subclass) return NO; // Even if the class implements the selector, it doesn't override itself.

AsyncDisplayKit/Private/ASLayoutTransition.mm

@@ -11,16 +11,17 @@
 //
 
 #import "ASLayoutTransition.h"
-#import "ASLayout.h"
-#import "ASThread.h"
-#import "ASDisplayNode+Beta.h"
 
+#import "ASDisplayNode+Beta.h"
+#import "NSArray+Diffing.h"
+
+#import "ASLayout.h"
 #import "ASDisplayNodeInternal.h" // Required for _insertSubnode... / _removeFromSupernode.
 
 #import <queue>
 #import <memory>
 
-#import "NSArray+Diffing.h"
+#import "ASThread.h"
 #import "ASEqualityHelpers.h"
 
 /**

AsyncDisplayKit/Private/Layout/ASLayoutElementStylePrivate.h

@@ -0,0 +1,29 @@
+//
+//  ASLayoutElementStylePrivate.h
+//  AsyncDisplayKit
+//
+//  Copyright (c) 2014-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+
+#pragma once
+
+#import "ASObjectDescriptionHelpers.h"
+
+@interface ASLayoutElementStyle () <ASDescriptionProvider>
+
+/**
+ * @abstract The object that acts as the delegate of the style.
+ *
+ * @discussion The delegate must adopt the ASLayoutElementStyleDelegate protocol. The delegate is not retained.
+ */
+@property (nullable, nonatomic, weak) id<ASLayoutElementStyleDelegate> delegate;
+
+/**
+ * @abstract A size constraint that should apply to this ASLayoutElement.
+ */
+@property (nonatomic, assign, readonly) ASLayoutElementSize size;
+
+@end

AsyncDisplayKit/Private/Layout/ASLayoutSpecPrivate.h

@@ -12,8 +12,9 @@
 
 
 #import "ASInternalHelpers.h"
-#import "ASEnvironmentInternal.h"
+
 #import "ASThread.h"
+#import "ASEnvironmentInternal.h"
 
 NS_ASSUME_NONNULL_BEGIN
 

AsyncDisplayKit/Private/Layout/ASLayoutSpecUtilities.h

@@ -8,13 +8,13 @@
 //  of patent rights can be found in the PATENTS file in the same directory.
 //
 
+#import <UIKit/UIKit.h>
+
 #import <algorithm>
 #import <functional>
 #import <type_traits>
 #import <vector>
 
-#import <UIKit/UIKit.h>
-
 namespace AS {
   // adopted from http://stackoverflow.com/questions/14945223/map-function-with-c11-constructs
   // Takes an iterable, applies a function to every element,