mac: Remove unused includes of scoped_nsobject.h.

chrome/browser/ui/cocoa/draggable_button_mixin.mm

Index: chrome/browser/ui/cocoa/draggable_button_mixin.mm
diff --git a/chrome/browser/ui/cocoa/draggable_button_mixin.mm b/chrome/browser/ui/cocoa/draggable_button_mixin.mm
index 934e429f6640ddf0fb0051ecd1450c2b460d5a4c..986f5e92b70c57455e5bfd4040c1454e32c13585 100644
--- a/chrome/browser/ui/cocoa/draggable_button_mixin.mm
+++ b/chrome/browser/ui/cocoa/draggable_button_mixin.mm
@@ -7,9 +7,6 @@
 #include <cmath>
 
 #include "base/logging.h"
-#import "base/mac/scoped_nsobject.h"
-
-namespace {
 
 // Code taken from <http://codereview.chromium.org/180036/diff/3001/3004>.
 // TODO(viettrungluu): Do we want common, standard code for drag hysteresis?
@@ -17,8 +14,6 @@ const CGFloat kWebDragStartHysteresisX = 5.0;
 const CGFloat kWebDragStartHysteresisY = 5.0;
 const CGFloat kDragExpirationTimeout = 0.45;
 
-}
-
 // Private /////////////////////////////////////////////////////////////////////
 
 @interface DraggableButtonImpl (Private)