[Mac][Material Design] Change bookmark chevron icon size to 8x8.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.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.
 
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.h"
 
 #include <stddef.h>
 
 #import "base/mac/bundle_locations.h"
 #import "base/mac/foundation_util.h"
@@ skipping 890 matching lines @@
 
 - (IBAction)importBookmarks:(id)sender {
   chrome::ShowImportDialog(browser_);
 }
 
 - (NSButton*)offTheSideButton {
   return offTheSideButton_;
 }
 
 - (NSImage*)offTheSideButtonImage:(BOOL)forDarkMode {
-  const int kIconSize = 16;
+  const int kIconSize = 8;
   SkColor vectorIconColor = forDarkMode ? SkColorSetA(SK_ColorWHITE, 0xCC)
                                         : gfx::kChromeIconGrey;
   return NSImageFromImageSkia(
       gfx::CreateVectorIcon(gfx::VectorIconId::OVERFLOW_CHEVRON,
                             kIconSize,
                             vectorIconColor));
 }
 
 #pragma mark Private Methods
 
@@ skipping 2165 matching lines @@
 - (id<BookmarkButtonControllerProtocol>)controllerForNode:
     (const BookmarkNode*)node {
   // See if it's in the bar, then if it is in the hierarchy of visible
   // folder menus.
   if (bookmarkModel_->bookmark_bar_node() == node)
     return self;
   return [folderController_ controllerForNode:node];
 }
 
 @end