[Mac] Refactor Cocoa fullscreen code

chrome/browser/ui/cocoa/download/download_shelf_controller.mm

Index: chrome/browser/ui/cocoa/download/download_shelf_controller.mm
diff --git a/chrome/browser/ui/cocoa/download/download_shelf_controller.mm b/chrome/browser/ui/cocoa/download/download_shelf_controller.mm
index 617b58c9212b82487644d4e6aaac5c744f194169..3467b0668d97982e829d918af8831b0bf5a4a9ae 100644
--- a/chrome/browser/ui/cocoa/download/download_shelf_controller.mm
+++ b/chrome/browser/ui/cocoa/download/download_shelf_controller.mm
@@ -20,7 +20,6 @@
 #include "chrome/browser/ui/cocoa/download/download_item_controller.h"
 #include "chrome/browser/ui/cocoa/download/download_shelf_mac.h"
 #import "chrome/browser/ui/cocoa/download/download_shelf_view_cocoa.h"
-#import "chrome/browser/ui/cocoa/presentation_mode_controller.h"
 #include "content/public/browser/download_item.h"
 #include "content/public/browser/download_manager.h"
 #import "third_party/google_toolbox_for_mac/src/AppKit/GTMNSAnimation+Duration.h"
@@ -130,15 +129,13 @@ const NSSize kHoverCloseButtonDefaultSize = { 18, 18 };
                         name:NSViewFrameDidChangeNotification
                       object:[self view]];
 
-  // These notifications are declared in fullscreen_controller, and are posted
-  // without objects.
   [defaultCenter addObserver:self
                     selector:@selector(willEnterFullscreen)
-                        name:kWillEnterFullscreenNotification
+                        name:NSWindowWillEnterFullScreenNotification
                       object:nil];
   [defaultCenter addObserver:self
                     selector:@selector(willLeaveFullscreen)
-                        name:kWillLeaveFullscreenNotification
+                        name:NSWindowWillExitFullScreenNotification
                       object:nil];
   [self installTrackingArea];
 }