Merge from revision 35723 from main branch plus NSCell allowsUndo flag extract from xib

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/gui/branches/gnustep_testplant_branch@35724 72102866-910b-0410-8b05-ffd578937521

Source/NSControl.m

@@ -49,6 +49,7 @@
 #import "AppKit/NSTextView.h"
 #import "AppKit/NSWindow.h"
 #import "GSBindingHelpers.h"
+#import "NSViewPrivate.h"
 
 /*
  * Class variables
@@ -1120,3 +1121,14 @@ static NSNotificationCenter *nc;
 }
 
 @end
+
+@implementation NSControl(KeyViewLoop)
+
+- (void) _setUpKeyViewLoopWithNextKeyView: (NSView *)nextKeyView
+{
+  // Controls are expected to have no subviews
+  //NSLog(@"%@@%p -_setUpKeyViewLoopWithKeyKeyView:%@@%p", [self class], self, [nextKeyView class], nextKeyView);
+  [self setNextKeyView: nextKeyView];
+}
+
+@end