ObserverList::HasObserver now takes a const pointer.

chrome/browser/ui/ash/screenshot_taker.h

 // Copyright (c) 2012 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 CHROME_BROWSER_UI_ASH_SCREENSHOT_TAKER_H_
 #define CHROME_BROWSER_UI_ASH_SCREENSHOT_TAKER_H_
 
 #include "ash/screenshot_delegate.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
@@ skipping 49 matching lines @@
   void HandleTakePartialScreenshot(aura::Window* window,
                                    const gfx::Rect& rect) override;
   bool CanTakeScreenshot() override;
 
   void ShowNotification(
       ScreenshotTakerObserver::Result screenshot_result,
       const base::FilePath& screenshot_path);
 
   void AddObserver(ScreenshotTakerObserver* observer);
   void RemoveObserver(ScreenshotTakerObserver* observer);
-  bool HasObserver(ScreenshotTakerObserver* observer) const;
+  bool HasObserver(const ScreenshotTakerObserver* observer) const;
 
  private:
   friend class ash::test::ScreenshotTakerTest;
 
   void GrabWindowSnapshotAsyncCallback(
       base::FilePath screenshot_path,
       bool is_partial,
       int window_idx,
       scoped_refptr<base::RefCountedBytes> png_data);
   void GrabPartialWindowSnapshotAsync(aura::Window* window,
@@ skipping 25 matching lines @@
   base::FilePath screenshot_directory_for_test_;
   std::string screenshot_basename_for_test_;
   Profile* profile_for_test_;
 
   base::WeakPtrFactory<ScreenshotTaker> factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenshotTaker);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_SCREENSHOT_TAKER_H_