Clean up a few more unused globals.

content/browser/renderer_host/render_widget_host_view_mac.mm

 // 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 
 #import <objc/runtime.h>
 #include <QuartzCore/QuartzCore.h>
 
 #include "base/basictypes.h"
@@ skipping 171 matching lines @@
 - (void)windowDidChangeBackingProperties:(NSNotification*)notification;
 - (void)windowChangedGlobalFrame:(NSNotification*)notification;
 - (void)drawBackingStore:(BackingStoreMac*)backingStore
                dirtyRect:(CGRect)dirtyRect
                inContext:(CGContextRef)context;
 - (void)updateSoftwareLayerScaleFactor;
 - (void)checkForPluginImeCancellation;
 - (void)updateTabBackingStoreScaleFactor;
 @end
 
-// NSEvent subtype for scroll gestures events.
-static const short kIOHIDEventTypeScroll = 6;
-
 // A window subclass that allows the fullscreen window to become main and gain
 // keyboard focus. This is only used for pepper flash. Normal fullscreen is
 // handled by the browser.
 @interface PepperFlashFullscreenWindow : UnderlayOpenGLHostingWindow
 @end
 
 @implementation PepperFlashFullscreenWindow
 
 - (BOOL)canBecomeKeyWindow {
   return YES;
@@ skipping 3641 matching lines @@
   return YES;
 }
 
 - (BOOL)isOpaque {
   if (renderWidgetHostView_->use_core_animation_)
     return YES;
   return [super isOpaque];
 }
 
 @end