Add a warning if [super layout] is not called (which causes big problems for ASLayout.)

AsyncDisplayKit/ASDisplayNode+Subclasses.h

@@ -81,7 +81,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @discussion Subclasses override this method to layout all subnodes or subviews.
  */
-- (void)layout;
+- (void)layout ASDISPLAYNODE_REQUIRES_SUPER;
 
 /**
  * @abstract Called on the main thread by the view's -layoutSubviews, after -layout.

AsyncDisplayKit/ASEditableTextNode.mm

@@ -186,6 +186,7 @@
 {
   ASDisplayNodeAssertMainThread();
 
+  [super layout];
   [self _layoutTextView];
 }