[Mac] Refactor Immersive Fullscreen Logic

ui/base/cocoa/tracking_area.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_BASE_COCOA_TRACKING_AREA_H_
 #define UI_BASE_COCOA_TRACKING_AREA_H_
 
 #import <AppKit/AppKit.h>
 
 #include "base/mac/scoped_nsobject.h"
@@ skipping 17 matching lines @@
              owner:(id)owner
           userInfo:(NSDictionary*)userInfo;
 
 // Prevents any future messages from being delivered to the |owner|.
 - (void)clearOwner;
 
 // Watches |window| for its NSWindowWillCloseNotification and calls
 // |-clearOwner| when the notification is observed.
 - (void)clearOwnerWhenWindowWillClose:(NSWindow*)window;
 
+// Returns YES if the mouse is inside the tracking area's rect. |view| is the
+// NSView the tracking area is attached to.
+- (BOOL)mouseInsideTrackingAreaForView:(NSView*)view;
+
 @end
 
 // Scoper //////////////////////////////////////////////////////////////////////
 
 namespace ui {
 
 // Use an instance of this class to call |-clearOwner| on the |tracking_area_|
 // when this goes out of scope.
 class UI_BASE_EXPORT ScopedCrTrackingArea {
  public:
   // Takes ownership of |tracking_area| without retaining it.
   explicit ScopedCrTrackingArea(CrTrackingArea* tracking_area = nil);
   ~ScopedCrTrackingArea();
 
   // This will call |scoped_nsobject<>::reset()| to take ownership of the new
   // tracking area.  Note that -clearOwner is NOT called on the existing
   // tracking area.
   void reset(CrTrackingArea* tracking_area = nil);
 
   CrTrackingArea* get() const;
 
  private:
   base::scoped_nsobject<CrTrackingArea> tracking_area_;
   DISALLOW_COPY_AND_ASSIGN(ScopedCrTrackingArea);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_COCOA_TRACKING_AREA_H_