[Mac] Move UI item validation to UserInterfaceItemCommandHandler.

chrome/browser/ui/cocoa/chrome_event_processing_window.mm

Index: chrome/browser/ui/cocoa/chrome_event_processing_window.mm
diff --git a/chrome/browser/ui/cocoa/chrome_event_processing_window.mm b/chrome/browser/ui/cocoa/chrome_event_processing_window.mm
index b7b437d923f67200e1a961bb126a05312fb709a3..922737873b00108f51e76b891318955880911726 100644
--- a/chrome/browser/ui/cocoa/chrome_event_processing_window.mm
+++ b/chrome/browser/ui/cocoa/chrome_event_processing_window.mm
@@ -45,6 +45,15 @@
   return [super performKeyEquivalent:event];
 }
 
+- (void)commandDispatch:(id)sender {
+  [commandDispatcherDelegate_ commandDispatch:sender window:self];
+}
+
+- (void)commandDispatchUsingKeyModifiers:(id)sender {
+  [commandDispatcherDelegate_ commandDispatchUsingKeyModifiers:sender
+                                                        window:self];
+}
+
 // NSWindow overrides.
 
 - (BOOL)performKeyEquivalent:(NSEvent*)event {
@@ -56,4 +65,12 @@
     [super sendEvent:event];
 }
 
+// NSWindow overrides (NSUserInterfaceValidations implementation).
+
+- (BOOL)validateUserInterfaceItem:(id<NSValidatedUserInterfaceItem>)item {
+  return
+      [commandDispatcherDelegate_ validateUserInterfaceItem:item window:self] &&
+      [super validateUserInterfaceItem:item];
+}
+
 @end  // ChromeEventProcessingWindow