[Mac][Material Design] Add MD hover to bookmark items in menus.

chrome/browser/ui/cocoa/bookmarks/bookmark_button_cell.mm

 // 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.
 
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_button_cell.h"
 
 #include "base/logging.h"
 #include "base/strings/sys_string_conversions.h"
 #include "chrome/browser/ui/cocoa/bookmarks/bookmark_bar_constants.h"
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_button.h"
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_context_menu_cocoa_controller.h"
 #include "chrome/grit/generated_resources.h"
 #import "components/bookmarks/browser/bookmark_model.h"
 #include "content/public/browser/user_metrics.h"
+#import "ui/base/cocoa/nsview_additions.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 #include "ui/base/material_design/material_design_controller.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/resources/grit/ui_resources.h"
 
 using base::UserMetricsAction;
 using bookmarks::BookmarkNode;
 
 namespace {
 
@@ skipping 361 matching lines @@
   }
 }
 
 - (int)verticalTextOffset {
   if (!ui::MaterialDesignController::IsModeMaterial()) {
     return 0;
   }
   return -1;
 }
 
+- (CGFloat)hoverBackgroundVerticalOffsetInControlView:(NSView*)controlView {
+  // In Material Design on Retina, and not in a folder menu, nudge the hover
+  // background by 1px.
+  const CGFloat kLineWidth = [controlView cr_lineWidth];
+  if ([self tag] == kMaterialStandardButtonTypeWithLimitedClickFeedback &&
+      ![self isFolderButtonCell] && kLineWidth < 1) {
+    return -kLineWidth;
+  }
+  return 0.0;
+}
+
+
 @end