[Mac] Revert to using the public API to display notification icons

chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm

 // Copyright 2016 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/notifications/notification_builder_mac.h"
 
 #import <AppKit/AppKit.h>
 
 #include "base/mac/mac_util.h"
 #include "base/mac/scoped_nsobject.h"
@@ skipping 114 matching lines @@
 - (NSUserNotification*)buildUserNotification {
   base::scoped_nsobject<NSUserNotification> toast(
       [[NSUserNotification alloc] init]);
   [toast setTitle:[notificationData_ objectForKey:kNotificationTitle]];
   [toast setSubtitle:[notificationData_ objectForKey:kNotificationSubTitle]];
   [toast setInformativeText:[notificationData_
                                 objectForKey:kNotificationInformativeText]];
 
   // Icon
   if ([notificationData_ objectForKey:kNotificationImage]) {
-    if ([toast respondsToSelector:@selector(_identityImage)]) {
-      if ([[NSImage class] conformsToProtocol:@protocol(NSSecureCoding)]) {
-        NSImage* image = [notificationData_ objectForKey:kNotificationImage];
-        [toast setValue:image forKey:@"_identityImage"];
-      } else {  // NSImage only conforms to NSSecureCoding from 10.10 onwards.
-        base::scoped_nsobject<NSImage> image([[NSImage alloc]
-            initWithData:[notificationData_ objectForKey:kNotificationImage]]);
-        [toast setValue:image forKey:@"_identityImage"];
-      }
-      [toast setValue:@NO forKey:@"_identityImageHasBorder"];
+    if ([[NSImage class] conformsToProtocol:@protocol(NSSecureCoding)]) {
+      NSImage* image = [notificationData_ objectForKey:kNotificationImage];
+      [toast setContentImage:image];
+    } else {  // NSImage only conforms to NSSecureCoding from 10.10 onwards.
+      base::scoped_nsobject<NSImage> image([[NSImage alloc]
+          initWithData:[notificationData_ objectForKey:kNotificationImage]]);
+      [toast setContentImage:image];
     }
   }
 
   // Buttons
   if ([toast respondsToSelector:@selector(_showsButtons)]) {
     DCHECK([notificationData_ objectForKey:kNotificationCloseButtonTag]);
     DCHECK([notificationData_ objectForKey:kNotificationSettingsButtonTag]);
     DCHECK([notificationData_ objectForKey:kNotificationOptionsButtonTag]);
 
     [toast setValue:@YES forKey:@"_showsButtons"];
@@ skipping 76 matching lines @@
   };
 
   return toast.autorelease();
 }
 
 - (NSDictionary*)buildDictionary {
   return [[notificationData_ copy] autorelease];
 }
 
 @end